Michael weighs and values some 14K gold hoop earrings, Lazooli’s 18K rose gold earrings, and his old platinum wedding band.
Value = weight of jewelry in grams X purity of gold in decimal form X gold price per gram.
Purity = karat / 24
Price per gram = price per troy ounce / 31.1
You will need:
1) a gram scale, like this: http://amzn.to/119zlU6
2) the gold price (http://lazooli.com, http://goldprice.org)
3) a calculator
4) the purity (or karat) of your jewelry – look for the stamp (10K, 14K, 18K, 22K, etc)
Shameless plug: note the melt value of those other 14K hoops ($99) compared to their price ($320, which was the best I could find as a retail customer). Only 30% of my money went towards gold – 15% would be typical.
Compare that to our high-end 18K rose gold hoops: melt value of $278 vs retail price of $440. A full 62.5% of the price goes towards pure gold: http://lazooli.com/products/rose-gold-18k-hoops-2-by-3mm