18k gold refers to the range of gold content greater than or equal to 750.0‰ but less than 9 16.0‰. Pt50 is not available in the national standard or market. It should be PT950, which means platinum greater than or equal to 950.0‰ and less than 990.0‰.
This paper discusses the differences from four aspects: material, value, usage scenario and purchase reference.
1. Material difference: According to the national standard GB 11887-20 1 2 "Provisions and Naming Methods of Precious Metals in Jewelry", it was approved and released by the National Standardization Administration Committee in February of 20120/5.
Purity is expressed as the lowest value and there should be no negative tolerance. The purity range of precious metals and their alloys is shown in the table.
18K gold has two common colors: rose gold and white, which are customarily called 18K gold and 18K platinum.
The main component of 18K gold is gold (Au), and now the gold content of most 18K white is 75%. In addition, copper, nickel, zinc and other materials are added to make the natural color white with yellow tone, and then rhodium plating is carried out to make the color whiter and more lasting. In some exquisite objects, palladium and silver are added to gold. This gold-palladium alloy is all white and does not need electroplating. The colors inside and outside are exactly the same, but the cost is high, which is rarely used by domestic merchants.
The main component of Pt950 is platinum (Pt), which is generally platinum plus copper, but also platinum plus gold.
Second, the value difference: 18k gold price is lower than Pt950, and the market price fluctuates. I won't give examples here. The price difference is that the price of platinum is already high, the proportion of high-priced materials containing Pt950 is larger, and the processing of platinum is more difficult.
Third, the difference between the use scenes: 18K gold is widely used as a mosaic substrate for various gems, with low cost and high hardness, and is an ideal mosaic material.
Pt950 platinum is mostly used to make pure platinum jewelry, and a small amount is used for inlay, which is difficult to process and can keep its true color well.
4. Selection reference: In the case of setting diamonds or other jewels, it is recommended to choose 18K gold, which has higher hardness and is not easy to deform, and the inlaid gems are more solid and reliable. 18K gold is more cost-effective. However, 18K gold and white faded after wearing, and the internal and external colors were inconsistent. 18K rose gold is its true color, and the internal and external colors are consistent after wearing.
If platinum must be used as inlay material, it is recommended to use Pt900. Generally speaking, the processing difficulty of platinum is much higher than that of 18K gold.