18gold likely refers to 18karat gold, which is a common measure of gold purity、Here's some information about 18karat gold:

1、Purity: 18karat gold is 75% pure gold (18 parts gold out of 24)、The remaining 25% consists of other metals, typically copper, silver, or nickel.

2、Color: Depending on the alloying metals used, 18karat gold can appear in various colors:
Yellow gold
White gold
Rose gold
Green gold

3、Durability: It's more durable than higher karat gold (like 24karat) but less durable than lower karat gold (like 14karat).

4、Value: 18karat gold is considered highquality and is often used in fine jewelry.

5、Markings: Jewelry made of 18karat gold may be marked with 18K, 18kt, 750 (the European standard), or AU750.

6、Applications: Commonly used in rings, necklaces, bracelets, and other fine jewelry pieces.

7、Cost: It's more expensive than lower karat gold but less expensive than 22karat or 24karat gold.

If you meant something else by 18gold, please provide more context so I can give you a more accurate response.