Purple gold is a precious metal noted for its vibrant purple color. More precisely, purple gold is an alloy of pure yellow gold mixed with aluminum and (sometimes) traces of other metals.
Today, we’re taking a deep dive into this lesser known gold color. Learn interesting facts such as when purple gold was invented, what it’s used for, and where you can get some. Let’s go!
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1. Purple Gold is a Real Gold Alloy
Despite its distinctly ungolden hue, purple gold is a real gold alloy. This fact was verified by the World Gold Council in 2001.
The standard formula for purple gold is 19 karats pure (79% gold). This is a higher gold karat purity than you usually see in gold jewelry alloys, which typically use no more than 18 karats (75% gold).
Purple gold has greater purity because gold-aluminum alloys are brittle – that is, hard but prone to breaking or shattering. Adding a little extra gold content to the mix helps to reduce this brittleness.
Just as with alloys of yellow gold, rose gold, and white gold, purple gold maintains its color all the way through.
This is in contrast to black gold, which is black on its surface, but normal yellow gold underneath.
2. Purple Gold is Unlike Other Jewelry Metals
Purple gold is a special class of alloy known as an intermetallic compound, which has different properties to normal jewelry alloys like yellow gold, white gold, and sterling silver.
Most jewelry alloys are malleable, which is what lets them be formed into different shapes without cracking under the strain. Malleability is also why you can drop a piece of regular gold, silver, or platinum jewelry on a hard floor, and not have to worry about it breaking.
Intermetallics, on the other hand, are brittle, inflexible, and fragile. Meaning if you dropped a piece of purple gold jewelry, you wouldn’t have the same peace of mind that it survived the fall.
Fans of purple gold tolerate this drawback because its purple color is so uniquely beautiful.
3. Purple Gold Jewelry is a Recent Invention
Purple gold was discovered in 1892 by the English metallurgist William Chandler Roberts-Austen. This makes it slightly older than white gold, which was invented in the early 1900s, and around the same age as rose gold.
However, purple gold jewelry is a much more recent development. Until the turn of the millennium, there was no way to make any kind of durable or practical jewelry from purple gold – it was simply too fragile.
After 23 years of thorough research, the Singaporean metallurgist professor Loh Peng Chum invented a purple gold alloy that was capable of being used in jewelry. Some variations of this alloy contained palladium or nickel in addition to gold and aluminum.
Professor Loh filed a patent for his alloy formulas in 2000, and approached Aspial Corporation Limited, the owner of several jewelry chain stores in Singapore, to commercialize his invention.
Lee Hwa Jewellery, an Aspial subsidiary, launched the world’s first purple gold jewelry line later that year.
4. Purple Gold Has Limited Jewelry Applications
The only way to make jewelry out of an intermetallic like purple gold is through casting. This metalworking technique involves pouring molten metal directly into a jewelry mold, where it solidifies into the mold’s shape.
Purple gold is too brittle to survive other techniques like forging, hammering, drawing, or soldering.
This limits the types of jewelry that can be achieved with purple gold. For example, you can’t get a purple gold necklace chain (as this would be formed by soldering) or a purple gold cuff bracelet (as these are typically formed by hammering).
While rings can be (and usually are) made via the casting method, purple gold isn’t that suitable for ring bands, either. A purple gold ring band would be at perpetual risk of breaking, due to how often your hand comes into contact with solid surfaces. One hard knock could be all it takes.
In a sense, jewelers treat purple gold more like a gemstone than a metal. While it can’t really be made into functional jewelry parts, it can enhance the aesthetic value of a piece of jewelry by being set inside a functional part.
For instance, a piece of cast and polished purple gold looks amazing in a white gold ring setting, or set in yellow gold and worn as a pendant.
5. You Can Buy Purple Gold Jewelry Online
Though not as easy as buying yellow, white, or rose gold, it’s possible to buy authentic purple gold jewelry online.
Based in Singapore, Lee Hwa Jewellery is the original and most well-known vendor of purple gold. Their shipping information page states that international delivery is offered on a “case-by-case basis”. However, when we emailed Lee Hwa asking if they delivered to the United States, we didn’t receive a reply.
Another notable vendor is the Japanese company Jewelry Miura. According to their English website, Jewelry Miura has been selling the “Cierin” brand of purple gold in Japan since 2009. This 18k purple gold alloy uses 75% yellow gold and 25% aluminum, and is verified as real gold by the Japan Mint.
Unlike Lee Hwa, Jewelry Miura replied to our enquiry and confirmed that they deliver to the US. The catch is that a large part of their eCommerce store is in Japanese. But if you can read Japanese, know someone who does, or are willing to trust your luck to Google Translate, then this could be an option for getting your hands on some purple gold jewelry.
If you see stores selling what look like solid purple gold rings, then be aware that these aren’t made from genuine purple gold alloy. It’s another kind of metal that’s been treated with purple surface plating. This purple plating isn’t permanent and will wear off over time.
6. You Can Make Your Own Purple Gold
That is, you can if you have the right metallurgical equipment and technological expertise, and are willing to put in the time and effort.
If this is a subject that interests you and you have an hour to spare, we highly recommend watching this informative YouTube video, in which content creator NileRed documents his efforts to create purple gold by following Professor Loh’s original alloy formulas.
After many attempts, NileRed successfully completed his mission to make purple gold, and cast and polished it into a beautiful ring. Since solid purple gold rings can’t be bought in stores or online, this is a truly unique creation.
We’re not sure how long this ring will survive the rigors of actually being worn – but there’s no denying that it looks absolutely stunning!
Thanks for reading and we hope you found this information of value. If you’d like to learn about another rare gold color, then check out our page on black gold.
Cover image credit: Jewelry Miura. Used with permission.