看到流行论坛里还是有一些JM搞不太清铂金(Platinum)、白金(White Gold，我称它为“白K金”)的区别，还顺便说说我喜欢的Sterling Silver


☆Gold☆

Gold is the oldest precious metal known to humankind. The metal's luster and remarkable properties have allowed it to be crafted into the world's most coveted and exquisite jewelry.

Gold is the world's most malleable (able to be pounded thin) and ductile (able to be drawn to a fine wire) of all metals. In its pure state, gold is too soft to be worn for jewelry, so it is usually mixed with other metals, such as silver, copper, nickel and zinc, to make it harder. A mixture of metals is called an alloy. The quantity of gold in an alloy is expressed in karats (abbreviated as k or kt). The following chart shows the proportion of pure gold in the most common karat counts:

24 karat: 100% pure gold

18 karat: 75% pure gold, 25% other metal(s)

14 karat: 58% pure gold, 42% other metal(s)

10 karat: 42% pure gold, 58% other metal(s)


Here are the most common colors of gold alloys and the metals used in making them:

Yellow Gold: Copper, Silver

Whithe Gold: Nickel, Zinc, Copper

Rose Gold: Copper

Green Gold: Silver, Zinc, Copper


→ Gold-Filled Jewelry

Gold-filled jewelry contains a layer of gold on a base metal. The percentage of gold must be at least 1/20 of the total weight of the piece.


→ Gold-Overlay Jewelry

Gold-overlay is a layering process in which a base metal is layered with gold. Gold-overlay jewelry is created with the following guidelines:
* Gold-overlay jewelry uses either 14kt or 10kt gold

→ Vermeil Jewelry

A Sterling silver base that is coated or plated with gold or gold alloy, Vermeil jewelry is created with the following guidelines:

* The gold coating must never be less than 10kt in fineness.

* The minimum thickness for this coating must be 3 microns. (A micron is a measurement of thickness used in the jewelry industry.)




☆Silver☆

Silver has a long and noble history, second only to that of gold. Popular as a jewelry metal for thousands of years, it is harder than gold and much more plentiful. The abundant supply and ease of working it make silver more affordable and a good alternative to gold and platinum (although it does tarnish and need polishing from time to time).

Sterling silver is a silver alloy with a fixed standard of purity. It consists of 925 parts silver (out of 1,000) and 75 parts copper. Like gold alloys, sterling silver can be used to plate other metals.



☆Platinum☆

Platinum is a pure, silvery-white metal prized for its rarity and beauty. The name "platina" came from Spanish explorers in 1735 and, ironically, means "silver with little value." Today, we know that ounce for ounce, platinum is the most expensive precious metal because of its rarity, purity and durability. Unlike gold, platinum usually is not alloyed with other metals.



所以，尽管国内将“铂金”(platinum)俗称“白金”，但它与带有K数的“白金”(white gold)是 totally different things。

白色K金并不是在铂金中加入其它物质，而是与黄色K金一样——都是在黄金中加入其它金属而制成（所以都属于合金），只是白色K金加入了能使黄金显现银白色的物质（也不是简单地在黄金表面镀一层银白色物质）。因此严格来说不存在纯的“白色黄金”，也就是没有“pure white gold”。白K金与黄K金的价格也相仿，或者贵一点点，但属同一档次，都比纯黄金低。

而铂金虽被民间称为“白金”，却不是“白色黄金”，只是呈现银白色而已。它比24K纯黄金更加稀有、价格更高。铂金首饰的纯度很高，不会存在带有K数的铂金。在宝石中，铂金通常与钻石相配做首饰。

其实区分铂金和白金的方法很简单，只要带有K数，那种“白金”就一定不是铂金，而是白K金(white gold)，铂金则应该标有“PT”；另外二者的价格也相差甚远。