Jewelry Buying Guide Metals

Jewelry Buying Guide

Diamonds

Precious Metals

The majority of Costco's jewelry is offered in three precious metal options: 14kt gold, 18kt gold, and 950 platinum. Discover the natural beauty and characteristics of each, and decide which one is best for you.

All 14kt and 18kt white gold that Costco offers has been rhodium plated to enhance luster, durability and brightness to the gold.

This does not affect the percentage of gold in the item. Some 950 platinum is also finished with rhodium for the same reason. If an item is rhodium plated, it will be noted on the product page.

Gold, silver, and platinum bullion products are offered for sale on Costco.com and in select Costco Warehouses. Our products range in weight from 10 grams to 100 ounces. All of these items are marked with their weight and purity. Each product is strategically sourced from key suppliers. These items are non-refundable and are not eligible for price adjustments. .

Gold

Due to its incredible luster and other characteristics, gold is the most sought-after metal in the jewelry industry. This precious metal is not only beautiful, it is naturally resistant to tarnish and corrosion. Most of all, gold has the rare quality of being dense yet still very malleable, which is ideal for crafting jewelry.

Although the density of pure gold makes it heavy, it is still very soft, so alloy metals are blended with the gold to increase its strength and durability. The addition of alloy metals makes gold jewelry much more wearable and long-lasting, and also allows for the creation of colored gold. Both 14kt gold and 18kt gold contain a percentage of alloy metals.

Gold is available in three beautiful colors—yellow, white, and rose. All three colors are produced the same way and have the same basic monetary value. White and rose gold are simply yellow gold blended with other metals to achieve their specific color. Each color has its own special beauty and characteristics. Whether you choose a clean brilliant white, pink-hued rose, or traditional yellow, your choice in gold should simply be a matter of preference.