To calculate the price of gold mathematically, you can use a simple equation. You'll need the following factors:

**Gold purity (carat):**You should know the carat of the gold you want to calculate the price for. We will use the carat as a percentage in this equation.

**Weight in grams:**You should know the weight of the gold you have in grams.

**Current gold price per gram:**You should know the current gold price per gram, which you can find online or from reputable financial sources.

The equation to calculate the value of gold is:

**Gold Value = (Weight in grams) × (Current gold price per gram) × manufacturing costs**

For example, if you have a piece of gold weighing 10 grams, and it is 18 karats, and the current price of gold per gram is $50, you can calculate the value of the gold as follows:

Gold Value = (10 grams) × (50 dollars/gram) × (18/24) = 10 × 50 = $500 plus manufacturing costs.

So, the value of this 18-karat gold piece weighing 10 grams would be $500. Remember that you can adjust the equation and use appropriate units according to the weight and the karat of the gold you have.

Gold Purity in Percentage:

- 24 carats: Contains 99.9%

- 22 carats: Contains approximately 91.6% (common for gold jewelry in global markets)

- 21 carats: Contains approximately 87.5%

- 18 carats: Contains approximately 75%

- 14 carats: Contains approximately 58.5%

- 10 carats: Contains approximately 41.7%

- 9 carats: Contains approximately 37.5%