Refer to the input text as context and select the correct relationship between 'gold mine' and 'gold' from the available options.
Options: member of, legal form, product/material produced, location of formation

The mine began production in 2013, and is the only primary gold mine in the world with annual production of more than one million ounces of gold (100% basis), at all-in sustaining costs below $700 per ounce.
product/material produced