750 on jewelry indicates that the jewelry metal comprises 75% of the primary metal. Usually, 750 is followed by the name of the primary metal, for instance, “750 gold” or “750 silver.” 925 and 950 are the most popular numbers on silver and platinum jewelry, respectively, so 750 is mostly used for gold.
Measuring Jewelry Fineness
Not all gold, silver, or platinum jewelry is created equal; they all have varying levels of fineness. Jewelry fineness measures how much fine jewelry content is in every jewelry piece in relation to alloys and impurities.
Jewelers constantly mix fine metals with other metals for reasons including the following.
- To improve the strength and hardness of soft metals like gold and silver.
- To alter a metal’s color, for instance, white gold and rose gold.
- To reduce the cost of jewelry by mixing it with cheaper metals.
Millesimal Fineness vs Karat
In the past, jewelers have expressed the fineness of jewelry in several ways. However, karat and millesimal fineness are the two most common means of measuring fineness.
Karat is used solely to measure gold’s fineness and works by dividing every piece into 24 parts. Therefore, 24-karat is pure, or 100% gold and anything less indicates that the gold piece contains other metal alloys. For instance, 14-karat gold contains 58.3% gold, while 10-karat gold contains 41.7% gold.
Millesimal fineness expresses metal purity in units of parts per 1000. In other words, every metal piece consists of 1000 parts of metal, and each element takes up a number in that 1000. Therefore, 1000 signifies 100% gold, while 585 signifies 58.5% gold.
You can convert millesimal fineness to karat using the table below:
| Millesimal Fineness | Karat |
| 999/1000 | 24 karats |
| 916 | 22 karats |
| 834 | 20 karats |
| 750 | 18 karats |
| 625 | 15 karats |
| 585 | 14 karats |
| 500 | 12 karats |
| 417 | 10 karats |
Properties of 750 Gold
750 gold has some properties that distinguish it from other gold purities:
1. Improved Durability
750 gold comprises 250 parts of stronger metals, significantly improving its durability. This alloyed gold withstands hits better in cases where 999 gold would bend, twist, or scratch easily.
2. Variety
750 gold affords users variety since it’s available in three colors:
- 750 White Gold— 750 parts gold mixed with 250 parts of white metals like silver or palladium. It often has a rhodium-plated finish.
- 750 Rose Gold— 750 parts gold mixed with 250 parts of copper.
- 750 Yellow Gold— 750 parts gold mixed with varying zinc, silver, and copper portions.
3. Price
The price is both a pro and con of 750 gold. The inclusion of metal alloys makes it considerably cheaper than 999 or 916 gold; however, it’s more expensive than 585 gold.
4. Popularity
999 gold jewelry is rare because gold is very soft and malleable, making it difficult for jewelers to work with. 585 and 750 are the two most popular gold purities in the jewelry industry. 585 gold is more prevalent in the United States, while 750 is more common in Europe.