Gold characteristics – what is a karat?
The term “scrap gold” refers to gold that must be melted and recycled before it is put to any use again. Your gold sample will have several characteristics that you have to define before you will be able to sell your scrap gold piece. These characteristics are listed below.
- Scrap gold weight: The weight of your gold sample. You can use a regular kitchen scale to measure it, but it is always better to find a digital gram scale. These are inexpensive and will give you more accurate results. Most often, gold is weighed in Troy ounces, which are different from regular ounces. 1 Troy ounce is roughly equal to 31.103 g (1.097 oz).
- Gold purity: This value describes the quality of your gold sample. The higher the gold purity is, the more pure gold does the scrap sample contain. For example, gold purity of 83.33% means that the sample consists of 83.33% pure gold and 16.67% of other metals, for example copper or zinc. Purity can also be measured in karats. 24K gold is the purest – it contains 99.99% gold. Each karat corresponds to 1/24th of the scrap gold mass, so for example an 18-karat sample will consist in 18/24 (75%) of gold and in 6/24 (25%) of other metals.
- Price per unit weight: You can obtain this value from various sources, for example websites with gold prices or your local gold dealer. Remember to input the correct unit of weight!
Gold value calculations example
Let’s assume you have done some tidying in your parents’ old house and have found a box of old golden jewelry. After careful inspection, you divided it into two batches – the first one is 18-karat gold (the most typical jewelry gold), and the second is 9-karat gold (a cheaper sort). You want to know how much it’s worth, should you try to sell it.
- Begin with weighing the scrap gold. Let’s assume that the 18-karat scrap gold weighs 120 g, while the 9-karat gold batch weighs 350 g.
- Recalculate the gold purity of each batch into percents. 18-karat gold has
18/24 = 75% pure gold, while the 9-karat gold has only
9/24 = 37.5% pure gold. If you have problems with this step, just use the fraction to percent calculator.
- Multiply the weight of each batch by the percentage of pure gold. In the first batch, you have exactly
120 * 0.75 = 90 g pure gold, and in the second one –
350 * 0.375 = 131.25 g pure gold.
- Add these weights. In total, you have
90 + 131.25 = 221.25 g pure gold.
- Check what is the current price of gold on the market. Let’s assume it is equal to $39 per gram.
- Finally, multiply the weight of pure gold by the unit price to obtain the gold value:
221.25 * 39 = 8628.75. Your box of golden jewelry is worth $8628.75!
- Of course, instead of performing all of these tedious calculations, it is easier to use our gold scrap calculator 🙂