All in the family: Adding pizzazz to family jewellery

By Llyn L. Strelau

We designed these earrings based on an inexpensive pair with glued-on coloured rhinestones given years ago to my client’s mother when he and his twin brother were children. Photos courtesy Llyn L. Strelau.

We designed these earrings based on an inexpensive pair with glued-on coloured rhinestones given years ago to my client’s mother when he and his twin brother were children. Photos courtesy Llyn L. Strelau.

Jewellery is all about symbolism and significance. After engagement and wedding rings, one of the most popular kinds of jewellery is that which celebrates family. This can be as old-school as the simulated birthstone rings those of a certain age will remember from the once-popular Consumer’s Distributing to pieces as exalted as Fabergé eggs! The challenge for a custom jeweller today is to design something that both represents the family or event and shows creativity.

The colours of love

An engagement ring featuring the birthstones of the bride and groom.

An engagement ring featuring the birthstones of the bride and groom.

The common thread among these types of commissions is celebration of the family and milestones, such as parenthood, achievements, anniversaries, remembrance, pets, and commemoration of a loved one.

Mother’s jewellery (or father’s for that matter) often incorporates gemstones signifying the birth months of family members. Rings, pendants, cufflinks, and pins are all options. If you are lucky, the birthstones look well together. (If you are not, you could have a gaudy combination of purple, green, red, and yellow in one piece that surely tells the story, but is not exactly attractive!) To avoid the old standard of gemstones all in a row, my approach is to find more creative designs in which to include the birthstones.

One option is to create a set of stacking rings, each embellished with one of the birthstone colours. The gems need not be the same shape, but of similar size. Or you could pavé-set one or more bands with several small stones. This can provide better economy when the client has the more expensive April, May, July, or September birth dates. This approach also makes it easy to add future rings as the family grows.

One can choose a large gem to represent the wearer, with either graduated sizes for the rest of the family according to age or a medium-size stone for the other parent and smaller ones for the children. For one client, I designed a pendant featuring three cherries inspired by the family orchard business. The colours weren’t realistic, but at least the blue zircon, aquamarine, and blue sapphire were birthstones of complementary colours. In another pendant, emerald represented the mother’s birthday, with peridot and opal for the children’s August and October birthdays, respectively. (I picked opal in this case, as it worked better with the other stones than pink tourmaline.) The father was born in April, so I pavé-set the ‘ribbon’ with many tiny diamonds, symbolically wrapping the family in affection.

When confronted with a project for a large family, it is difficult to avoid the mish-mash of colours. One ring for a grandmother started with her birthstone in the centre surrounded by her children’s. The four grandkids’ stones were set flanking the central flower with hand-engraved leaves and stems. Sometimes symbolism trumps esthetics! Perhaps more attractive is a bracelet made of three strands of flexible 18-karat yellow gold cable joined and clasped at the back, the birthstones bezel-set and attached on the top. The parents’ gems were the largest and sit on the centre strand. They had two children; one of these offspring provided three grandchildren, while the other had one. This design allows for additional stones, should the family grow.

Weaving a story

This ring is one example of how to incorporate 
a family’s birthstones. The centre stone 
symbolizes the grandmother, while the gems around it are for her children. The four 
grandkids’ stones flank the central flower 
and decorate hand-engraved leaves and stems.

This ring is one example of how to incorporate 
a family’s birthstones. The centre stone 
symbolizes the grandmother, while the gems around it are for her children. The four 
grandkids’ stones flank the central flower 
and decorate hand-engraved leaves and stems.

Combining birthstones with other personal symbols for the family can also help to make family jewellery more significant for the owners. A musical family chose a treble clef design for a pendant with a larger stone for the mother at the bottom and three for the children set in the centre. For a client who requested a pendant for his engineer/astronomy buff wife to celebrate their 21st anniversary, 
I incorporated a slice of Gibeon meteorite as the centre and set it in a yellow gold bezel with a 21-tooth, mechanical gear detail. I star-set the family birthstones to symbolize the constellation Orion. A small white gold crescent moon with blue sapphire eye completes the esthetic.

Sometimes numbers help tell a story. A client celebrating his 25th anniversary requested a ring for his wife. During our discussions regarding its design, he mentioned he had proposed all those years ago with a single red rose. Each year thereafter he added a rose to the bouquet he presented his wife on their anniversary. The ring features two rose gold carved blooms with stems (one for each of them) flanking a .25-carat bezel-set diamond. The side rims comprise eternity bands, set with 25 diamonds a piece, each one .01-carats, packing as much symbolism into this ring as possible.

Some jewellery is more about family history and sentiment. A client who typically purchases significant pieces came in one day with a tiny elephant carved from ivory or bone. It seemed an odd thing for her to own, let alone make into a piece of jewellery. She told me it was one of the few things she had that had belonged to her mother. After learning more about the piece and my client’s mother, I came up with a simple brooch featuring white gold mountain peaks, yellow gold foothills, a green gold palm tree, and red gold ground, all to support and frame her little elephant. We finished the brooch with a bezel-set carved moonstone moon face.

Dad loves frogs, hence these cufflinks featuring tourmaline frogs on a druzy uvarovite garnet pond. A carved elephant is the focal point of this brooch made in honour 
of a client’s mother. The piece features white gold mountain peaks, yellow gold foothills, a green gold palm tree, red gold ground, and a bezel-set carved moonstone moon face.

Dad loves frogs, hence these cufflinks featuring tourmaline frogs on a druzy uvarovite garnet pond.

For a client whose husband has a passion for frogs, I designed a pair of cufflinks featuring slices of druzy uvarovite garnet for the algae-covered pond that I set with a pair of carved tourmaline frogs perched on the margin. Tiny diamond dewdrops complete the picture.

Now in his mid-40s, a client commissioned a pair of earrings based on a gift he and his twin brother had given their mother when they were children: stylized Christmas trees with glued-on coloured rhinestones. Now a successful business man, my client requested we make her a pair of ‘real’ earrings that looked like the originals. Creating a rubber mould of the tree, we cast it in 18-karat yellow gold and set genuine family birthstones. We were able to create add-on sales by making cufflinks for each of the twins and pendants for their sisters, as well.

It is worthwhile to engage the client in the development of family jewellery designs. Some more than others can provide a great deal of input the designer can then filter and use for inspiration. I’m reminded of a commission for a client whose daughter was heading off to college in the United Kingdom. Being a very thoughtful man, he had written a few sentences that encapsulated for her his advice for life. After much discussion, we created a simple oval white gold plaque and had his words hand-engraved in a spiral, the phrases separated by flush-set black diamonds. The result was a very intimate piece she would wear daily, but that a casual observer would only perceive as pattern unless she invited closer inspection to reveal the sentiment. When his son went off to university, the same client commissioned a belt buckle, similarly engraved with another personal mantra.

People living in Victorian England used the ‘language of flowers’ to send highly detailed, though coded messages to lovers (and sometimes to those whom they spurned). I had a commission to design a locket that used this secret language to good effect. The base locket was sterling silver with a textured and oxidized background in a shiny frame. The bouquet was handcrafted of 3-D silver and fine gold flowers, combining a pansy (think of me), forget-me-nots (memories), a rose (true love), and daffodils (regard), with a larger rose as the bail.

Don’t forget dad

Self-portraits made by my client’s children are a touching keepsake for their father.

Self-portraits made by my client’s children are a touching keepsake for their father.

Unfortunately, family jewellery for dad does not offer as much scope for design. A mother of three boys requested cufflinks for their father. I suggested each of the boys draw self-portraits. She came back with three drawings that beautifully reflected the ages of the children with charming degrees of realism. Next, I scanned the images, combining them in graphics software and mirroring the scan to provide left and right images. I imported these into CAD software, converting the black lines of the portraits into cutters, which I used to create recessed areas into disk-shaped elements for the front of the cufflink. These were then milled and cast in 
19-karat white gold. (In the time before CAD, I would have had the design photo-etched into metal plates, rubber-moulded, and cast.) After clean-up, we filled the recesses with wax, attached sprues to the wax layer, and invested in the usual way.

Since 19-karat white gold has a higher melting point than 18-karat yellow gold, it is possible to cast it in place without affecting the white metal. The next stage was to file and sand the yellow gold layer down until only the image’s gold inlay was left. Since polished gold does not reveal colour contrast very well, we created a scrubbed sandpaper finish with the white gold edge bevelled and polished to frame the images. If budget had permitted (these were made in the days when platinum was twice the price of gold), we could have achieved even better colour contrast by using platinum instead of white gold with 22-karat gold for the inlay. The client was thrilled with the result and they have a family heirloom to pass down, though I wonder which son will get them.

Touching tributes

A reminder of a beloved pet, this piece includes a micro-mosaic portrait of a family’s German Shepherd bezel-set in a bracelet.

A reminder of a beloved pet, this piece includes a micro-mosaic portrait of a family’s German Shepherd bezel-set in a bracelet.

All family jewellery is a celebration, but sometimes it can be a bittersweet commemoration. For a client who lost a child to Sudden Infant Death Syndrome (SIDS), we created a brooch with branches of stylized baby’s breath accented with tiny white diamonds overlaid on a slice of rich blue lapis lazuli. It is a poignant reminder of a life cut tragically short.

Some people honour their pets after they’ve passed away by using paw prints taken by veterinarians. These impressions can be scanned in 3-D and converted into a CAD model. It is usually necessary to shrink the prints to a reasonable size, but once that is done, they can be milled and cast in silver or gold, providing lasting mementos of a favourite feline or man’s best friend.

As custom jewellers, we have the great privilege of becoming deeply involved in our client’s lives. Creating a personalized piece of jewellery that reflects and celebrates families and their special occasions provides joy for them and satisfaction for the designer. It is up to us to discover innovative and original ways to tell their story!

Llyn L. Strelau is the owner of Jewels by Design, a designer-goldsmith studio in Calgary established in 1984. His firm specializes in custom jewellery design for a local and international clientele. Strelau has received numerous design awards, including the American Gem Trade Association’s (AGTA’s) Spectrum Awards and De Beers’ Beyond Tradition—A Celebration of Canadian Craft. His work has also been published in Masters: Gemstones, Major Works by Leading Jewelers. Strelau can be reached via e-mail at designer@jewelsbydesign.com.

 

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Pearls of wisdom

Unravelling the complex world 
of appraising pearls

By Gina D’Onofrio

Signed Carlo Giuliano 
gold Etruscan revival necklace with cave pearls. Photo courtesy Heritage Auctions.

Signed Carlo Giuliano 
gold Etruscan revival necklace with cave pearls. Photo courtesy Heritage Auctions.

Pearls have been treasured for centuries as a symbol of wealth and nobility. Yet, they are no longer reserved for the privileged few. Today, we can all enjoy pearls of infinite variety and at any price.

Keeping up with the abundance of choice is the appraiser’s challenge. When we study pearl identification and grading, the primary focus is on natural, cultured saltwater, and freshwater pearls. Recognizing the variety can be difficult, but determining their value can be just as daunting. This is not a guide to pearl grading, however. If you are a practicing appraiser, we can safely assume you are a gemmologist who has studied pearl grading. Right? If not, I suggest you take a pearl grading class from a reputable gemmological school and consult some of the references listed at the end of this article.

A look back

Nucleated, unfinished freshwater cultured pearl strand. Photo courtesy King’s Ransom

Nucleated, unfinished freshwater cultured pearl strand. Photo courtesy King’s Ransom.

A discussion on pearl appraising cannot begin without mentioning the radical changes in supply and demand, starting with the introduction of the spherical cultured pearl in Japan by Kokichi Mikimoto in the early 20th century. More affordable than their natural counterparts, cultured pearls became a huge success, dominating the pearl industry until the 1960s. Freshwater Biwa pearls from Japan rode the next wave of popularity in the 1970s. Irregular ‘rice krispie’ Chinese freshwater pearls, cultured South Sea, and Tahitian pearls came to the fore in the ’80s, followed by larger, smooth-skinned freshwater ‘potato pearls.’ The 2000s were all about a myriad of new Chinese freshwater and Akoya pearl varieties.

There have been enormous developments in demand, perliculture, and supply, resulting in roller coaster price fluctuations. This can place an appraiser in some tricky situations. For example, how do you tell your client her 20-year-old cultured South Sea pearl strand has dropped in value… by less than half?! You could explain the increased number of pearl farms, subsequent oversupply, and competition has driven down the price. An alternative, though, may be to focus on the upside, which is her insurance premium will be greatly reduced.

Natural pearls have enjoyed renewed interest and a huge leap in value over the last decade. If you have a piece predating 1900, chances are the pearls are natural and significantly more valuable than cultured (assuming they were not replaced at a later date). Recommend your client submit the pearls to a lab for advanced testing. This will determine whether the pearls are cultured or natural, as well as the species.
Also, when inspecting older pearl necklaces, particularly graduated strands, take the time to study the smaller gems. There was a time in the early- to mid-20th century when cultured pearls where added to lengthen shorter, antique, natural pearl strands.

Unfortunately, testing can be prohibitive, so deciding to submit mixed strands to a lab is a judgment call for you and a gamble for your client. In addition, 
I do not recommend employing the services of your local radiologist, since they lack the skill and industry-specific equipment to properly X-ray the pearls and, more importantly, interpret the results. A word about old pearl laboratory reports: as with coloured gemstones, there have been new developments in pearl testing that may result in your conclusions differing from the report’s. For example, the first DNA test for pearls was introduced in 2013 for the three major pearl-producing oyster species: Pinctada margaritifera, Pinctada maxima, and Pinctada radiata. With that in mind, an updated report may be worthwhile for potentially valuable pearls.

China takes the lead

Fortunate appraisers may encounter rare species, such as the conch pearl shown here, which has its own grading criteria 
and may require consultation with an expert who is familiar with this particular gem. © Gemological Institute of America (GIA). Reprinted by permission.

Fortunate appraisers may encounter rare species, such as the conch pearl shown here, which has its own grading criteria 
and may require consultation with an expert who is familiar with this particular gem. © Gemological Institute of America (GIA). Reprinted by permission.

The rapid development of Chinese perliculture has greatly impacted the international pearl market. Recent Chinese pearl exports are in the range of 1000 to 1500 tons per year compared to Japan’s eight tons per year. Chinese freshwater cultured pearl varieties include tissue-nucleated, bead-nucleated in-mantle, and bead-nucleated in-body spherical, baroque, and fancy shapes, all of which are available in natural and treated colours.
Concurrently, there is a limited supply of finer-quality Chinese cultured freshwater and Akoya pearls (0.5 per cent of its annual export); their increased prices may overlap that of South Sea and Tahitian pearls. There seem to be new techniques in pearl culture and treatments every year, which impact the pearl supply chain and value. For example, the strand of hollow, Chinese freshwater ‘souffle’ pearls your client purchased three years ago may be extremely difficult to replace today, as the labour-intensive method used to produce them is no longer cost-effective and production is limited. When appraising these pearls, your choice may be to replace them with new old stock or an entirely different freshwater pearl strand of comparable quality and desirability. Make sure your reasoning and method of replacement are clearly described next to your value conclusion.

It is difficult to discuss Chinese freshwater pearls without mentioning Edison pearls. Introduced in 2012, these in-body, bead-nucleated freshwater pearls have become the darling of the pearl industry. Betty Sue King of King’s Ransom Pearls offered the following description: “The spectrum of peach, pink, rose, lavender, and metallic finishes simply dazzle the eye and work their magic. The best are the classic round shape due to similar nucleation techniques used for South Sea cultured pearls. Pricing is primarily determined by quality of nacre, symmetry of shape, surface, colour, and size.”

Combined with an oversupply of commercial qualities, China’s introduction of new varieties has steered other pearl-producing countries in new directions. For example, Japan and Vietnam are focused on producing ‘classic’ Akoya pearls of exceptional quality, which they believe cannot be matched by Chinese Akoyas. As a result, consumers benefit from a greater supply of these pearls, making it easier to find replacements for grandma’s fine mid-century cultured pearls with a thicker nacre. The same may be said for cultured South Sea and Tahitian pearls. The commercial end of the market is saturated with these varieties. Farmers are focused on producing pearls of higher quality with a thicker nacre to set themselves apart from the competition and this is sure to have an impact on price.

Origin matters

11- to 14-mm baroque natural colour Japanese Kasumi pearls. Photo courtesy Kojima Pearl Co.

11- to 14-mm baroque natural colour Japanese Kasumi pearls. Photo courtesy Kojima Pearl Co.

Much like Burmese ruby and Kashmir sapphire, some pearls’ country of origin may significantly impact its value. Case in point: Japanese Kasumi pearls from Lake Kasumigaura. These gems are cultured and harvested by a very small group of pearl farmers and trade at a significant premium over their Chinese freshwater counterparts. Currently, the entire harvest of Lake Kasumi pearls is less than 33 lbs (15 kilos) per year. Unfortunately, Chinese freshwater in-body pearls are being misrepresented as Japanese Kasumi pearls, leading to much confusion in the trade and among consumers. “Japanese Kasumi pearls command on average 10 times the price,” says Sarah Canizzaro of importer Kojima Pearl Co., in San Rafael, Calif. Provenance is a major factor appraisers must consider when valuing these pearls. Her advice is to obtain 
copies of the client’s purchase receipts with dates wherever possible.

You may encounter other cases of mistaken identity affecting value, such as
• 
saltwater Keshi versus freshwater Chinese ‘Keshi’ versus Japanese ‘Keshi’ versus American freshwater;
• 
cultured Akoya versus natural saltwater;
• 
cultured freshwater versus natural freshwater;
• 
cultured round Akoya versus cultured round freshwater; and
• 
mixed pearl strands of various species, either antique or contemporary.
How can you avoid making costly errors? First, meet the suppliers. Many of them specialize in certain varieties, so get to know who sells what. Find out where they exhibit. If you cannot attend the major trade shows, you may be able to visit them at a regional gem show closer to home. Second, stay current to the latest trends, developments in perliculture, and treatments. It is essential appraisers understand which colours occur naturally and which do not and why. Become familiar with industry jargon and trade names, such as ‘fireball,’ ‘coin,’ and ‘petal.’ They’re incorrect from a gemmological point of view, but allow you to conduct market research and communicate effectively with pearl vendors.

Remember, pearl prices are a moving target, so use price guides in conjunction with your market research. Attend gemmological conferences, read trade journals, and participate in online appraisal and pearl forums. I have listed some excellent resources at the end of this article.

Fortunate appraisers may encounter some of the rare species, such as conch pearl, quahog, abalone, melo melo, or cave pearl (not a typo). Look carefully and you will find most of these at the Tucson gem shows or your natural history museum. I was thrilled to see a Victorian gold necklace by Carlo Giuliano set with a fringe of cave pearls at Heritage Auctions. Each species is exotic and unique, with its own set of grading criteria that go far beyond the scope of this article. Suffice to say, if you encounter any of these pearls, consult an expert.

My hope is that by reading this article, appraisers will be willing to step outside their comfort zone to dis-cover more about these extraordinary gems. The leading pearl suppliers are a small community who are extremely knowledgeable and passionate about what they do. I encourage you to meet them, attend lectures, and read the references included here. Then share this information with your fellow appraisers. I’m sure they will reciprocate and together you can elevate the standard of this wonderful profession.

References and resources
1) Pearl Guide Forum, a source of pearl information (http://www.pearl-guide.com/forum/content.php).
2) Kojima Pearl blog by Sarah Canizzaro (http://www.kojima
pearl.com/japan-kasumi-pearl-harvest-2015/).
3) Gemguide, a resource for pricing gems (https://gem
guide.com/the-gemguide/pricing-and-editions/).
4) Accredited Gemologists Association (AGA) offers twice yearly lectures on the latest developments in gemmology (http://accreditedgemologists.org).
5) Pearls by Elisabeth Strack, a seminal work on the science and history of pearls.
6) Margaritalogia by Elisabeth Strack, an in-depth newsletter on developments in the world of pearls 
(http://www.gemmologisches-institut-hamburg.de).
7) Abstracts on pearl lectures from AGA’s 2011 conference (http://accreditedgemologists.org/pastevents/2011abstracts/Strack.php).

Gina D’Onofrio has provided gemmological and jewellery appraisal services since 1992. She is an accredited senior appraiser, master gemmologist appraiser (American Society of Appraisers) and certified senior member of National Association of Jewelry Appraisers. D’Onofrio is co-instructor for the American Society of Appraiser’s GJ-202 appraisal report writing for insurance coverage class. She may be contacted via e-mail at ginajewels@gmail.com.

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The alloyed truth (Part 6)

Using the right mix for the job

Part 6 of 6

By Llyn L. Strelau

A white gold setting for a white diamond may seem like a natural fit, but sometimes that’s not entirely the case. Photo courtesy Llyn L. Strelau

A white gold setting for a white diamond may seem like a natural fit, but sometimes that’s not entirely the case. Photo courtesy Llyn L. Strelau

Custom work is usually dictated by a client’s personal preference for metal colour and budget. I find younger clients may have only ever worn silver jewellery, more due to their financial situation than preference. When it comes time for a more valuable piece of jewellery, such as an engagement or wedding ring, they may just assume white gold or platinum is their best choice. This decision can also be influenced by current jewellery trends and mass advertising. However, I’ve found it can be useful to show them alternatives. Some skin tones and complexions are complemented by yellow metal rather than white, not to mention the fact some gemstones look better in one than the other.

White diamonds usually present better in white metal, although that’s not always the case, as you can see in the photo above. I recently made this 18-karat yellow gold organic engagement ring with a tree branch and birch leaf design holding a large oval diamond. My initial inclination was to set the diamond (it was an E colour) in a white gold bezel, but the client really wanted an all-yellow gold ring. Although I had my doubts, I later had to agree that once the diamond was set in a yellow gold bezel, it was a much more attractive piece as a whole.

I encourage my fellow designers to explore the spectrum of coloured metals. Use them to complement coloured gemstones, contrast with each other, and add individuality to your creations. That said, when making multicoloured gold pieces, be aware the colour of polished metal is subtle. For maximum contrast, a matte or textured surface can be preferable.

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The alloyed truth (Part 5)

Using the right mix for the job

Part 5 of 6

By Llyn L. Strelau

A bead-blasted green and rose gold ring, with a polished platinum round wire accent. Photo courtesy Llyn L. Strelau

A bead-blasted green and rose gold ring, with a polished platinum round wire accent. Photo courtesy Llyn L. Strelau

I have a word of caution when it comes to white gold alloys—choose your preferred mix carefully and stay with it if possible and here’s why. Thirty years ago, we made our own 18-karat white gold from a proprietary base metal mixture that we combined with pure gold in the shop. It was a dream metal to work with—its ductility and ability to be re-used several times while retaining its working properties were amazing. While it had a pretty good white colour when freshly polished, after a relatively short period, it acquired surface oxidation, leaving it a rather unattractive brownish tone. When used in combination with yellow gold for a two-tone piece, there was almost no difference between the yellow and white colour, even when the surfaces were matte finish. We could have rhodium-plated this, but it didn’t look very good and required periodical re-plating.

Twenty years ago, I switched exclusively to using a 19-karat white gold alloy. I buy this already mixed as casting grain from a Canadian supplier. It has its pros and cons. The colour is as close to platinum white as I have found. It neither changes colour with time nor does it require rhodium plating to look good. It provides excellent contrast when used in combination with yellow and rose gold. It also recasts well, provided some new material is added. Now for the cons—it contains nickel. It is also quite hard and requires some care in casting and annealing for fabrication. That said, it responds well to both soldering and especially laser welding.

Being limited to one white gold alloy is problematic, as there is always the risk the supplier will change the blend or stop making it altogether. Therefore, over the years, I have experimented with white gold alloys from a variety of suppliers to see if there is a better alternative to my current standard 19-karat. Some were excellent products, but there was one major roadblock to switching from the metal we were using: consistency. I used one of the alternate 19-karat white gold alloys to make an engagement ring for a client. The metal cast, worked, and polished beautifully and had a nice white colour, albeit not exactly the same as our standard alloy. There were no compelling benefits to switching, however, and I decided to stick with the existing alloy going forward. This decision proved to be a good one because two years later, the client returned to have a matching wedding band made. I had not recorded the fact we had used the new alloy for the original ring, and we made the new band in our usual blend only to realize the two rings simply did not match. We had to buy gold from the other supplier and remake the band. Not a good financial situation!

More to come of this story in Part 6.

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The alloyed truth (Part 4)

Using the right mix for the job

Part 4 of 6

By Llyn L. Strelau

Jewellery-specific technology and equipment have come a long way since the early 20th century. For instance, the development of induction melting furnaces using inert gas atmospheres has made it possible to combine metals in ways that were impossible previously. Preventing oxygen from contaminating these alloys is critical. Some blends are appropriate for cast pieces, but fabricating or repairing with a torch is not possible. They do respond well, however, to welding with laser machines.

Our industry lost a huge talent in the metallurgist/jeweller/alchemist Stephen Kretchmer when he was tragically killed in a vehicle accident in 2006. In his all-too-short life, he developed many innovative alloys. His heat-treatable platinum—which incorporated special heating and cooling techniques post casting and finishing—vastly increased the metal’s hardness and springiness to permit very secure tension setting of gemstones. Kretchmer also developed magnetic platinum alloys, which he used to create earrings with floating components suspended in magnetic fields. In addition, he came up with better purple and blue gold alloys, although gold mixed with aluminum or iron is extremely brittle and must be treated more like a gemstone than metal.

Rose gold has gained much popularity in recent years due to its use by larger commercial jewellery brands. Degrees of ‘pinkness’ can be achieved by varying the amounts of copper and silver in the alloy. Next to white gold, rose is the hardest of coloured alloys. It can also be more difficult to cast and fabricate when its components are not in the right proportions. That said, it com-bines well with pink, red, and earth-toned gemstones. I particularly like the combination of rose gold with white gold or platinum. The pink colour warms the white metal, while the white colour softens the intensity of the pink, creating good balance in a design.

Green gold is pure gold combined with pure silver. Both 14-karat and 18-karat alloys can offer a good green colour that is attractive when used to set green gemstones, especially those with a yellowish cast, such as some garnets and peridot. It is, however, the softest of the coloured alloys. Although it is easy to pavé- or bead-set gems in green gold, it is perhaps not the best material for delicate openwork designs that will be subjected to hard wear. It also combines well with rose gold for two-tone designs.

Yellow gold alloys offer a wide range of colour, achieved by varying the proportions of copper and silver. Adding more copper skews the colour to the rose end of the spectrum, while higher silver content makes it green. All yellow gold alloys contain trace elements of other metals to improve workability.

More to come of this story in Part 5.

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The alloyed truth (Part 3)

Using the right mix for the job

Part 3 of 6

By Llyn L. Strelau

‘Tierra’ pendant clasp in 18-karat green gold set with green tourmaline, golden beryl, and accented with a yellow diamond and golden green South Sea pearl drop. Photo courtesy Llyn L. Strelau

‘Tierra’ pendant clasp in 18-karat green gold set with green tourmaline, golden beryl, and accented with a yellow diamond and golden green South Sea pearl drop. Photo courtesy Llyn L. Strelau

Although North America has not adopted standards for nickel content, palladium alloys are also increasingly used here. Their colour is generally greyer than ‘silvery’ white and some of them are rather soft, which limits their use for some purposes. That said, the relatively low price of palladium can make them attractive options. Some palladium alloys comprise metals that are added to increase hardness. Here, the colour tends to be greyish and the techniques for casting and annealing are specialized. However, palladium alloys can offer a good alternative for some applications.

A jewellery colleague of mine in the Unites States has a patent pending for alloys combining palladium or platinum with small amounts of rhodium. They offer a very attractive white colour that does not require electroplating and has zero nickel content. The alloys also have improved hardness and durability compared to traditional platinum and palladium blends. Specialized techniques are required for producing the alloys and for their subsequent casting and manufacturing, but their development presents an exciting new frontier.

More to come of this story in Part 4.

Read the full article: The alloyed truth

 

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