This question is a bit tricky because it depends on what you're trying to measure! Here's why:

* An ounce is a unit of weight.

* A quarter is a unit of currency.

You can't directly convert currency into weight.

Here's what you *could* be asking:

* How many quarters weigh an ounce? This depends on the year and type of quarter. Older quarters are made of silver, which is heavier than the nickel-copper alloy used in modern quarters.

* How many quarters are worth an ounce of gold? This is possible, but it would involve calculating the value of gold and the value of a quarter, then comparing them.

Let me know if you can clarify your question, and I can give you a more precise answer!