It's wise to use a circuit breaker to determine if you put a trade on or not. 

One way to do that is to measure the volatility of the instrument in question. 

Many traders use the 20-Day ATR for that measurement. 

With Gold's volatility at $50, and the contract being 100 troy ounces, you're looking at $5,000 of daily volatility. 

If that's equal to your risk unit of 1/2 of 1%, then you need a $1,000,000 account to trade 1 COMEX Gold contract. 

Listen and see why you might not want to trade this contract using a tighter stop than $50.

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