Gold Purity: 375, 585 and 750
Purity shows how much pure gold an alloy contains, in thousandths. Gold of 585 purity holds 585 parts of gold in every 1,000, that is 58.5%. The rest is other metals such as silver, copper, palladium and zinc. They make the metal stronger and give it its color. Pure gold (999, 24 karat) is too soft for jewelry: a ring made of it would soon bend and scratch.
MJ. jewelry is made in 375, 585 and 750 gold. The purity of every piece is stated on its page.
Purity and karats
In Europe and America gold purity is often given in karats, where 24 karats is pure gold. The two convert easily:
| Purity | Karat | Pure gold | Other metals |
|---|---|---|---|
| 375 | 9K | 37.5% | 62.5% |
| 585 | 14K | 58.5% | 41.5% |
| 750 | 18K | 75% | 25% |
| 999 | 24K | 99.9% | — |
How 375, 585 and 750 differ
- Color. The higher the purity, the richer and warmer the yellow. Yellow gold of 750 purity looks clearly more golden than 375.
- Strength. The more other metals an alloy contains, the harder it is. 375 and 585 gold stand up to daily wear best; 750 is a little softer, yet strong enough for rings and earrings.
- Price. The cost per gram depends above all on the amount of pure gold, so the same design costs more in 750 than in 585, and more in 585 than in 375.
- Care. Alloys with less gold contain more copper and silver, so 375 gold may dull slightly over the years. A jeweler's cleaning brings the shine back.
Which purity to choose
- 585 is the most popular choice: strong, a beautiful color and a sensible price. Right for everyday rings, earrings and bracelets.
- 750 suits an engagement ring and pieces with larger diamonds: a noble color and more gold in every gram.
- 375 is for when price matters: delicate pieces with stones at an accessible cost.
White, yellow and rose gold
The color of gold does not depend on its purity: white, yellow and rose gold all come in 585 and in 750. The difference lies in the other metals of the alloy. Yellow gold contains silver and copper, rose gold more copper, and white gold palladium or other white metals. White gold is usually plated with rhodium for a bright white shine, and after a few years of wear the plating can be renewed.
How to tell the purity
The purity is usually stamped on the piece in a small hallmark: inside a ring, on a chain's clasp or on an earring's lock. You can see the purity of any MJ. piece on its page on the site, or ask at the boutique.
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