Space Mining: Ore Availability and Yield

[Ezra]

An exploratory prospecting vessel would make an interesting Traveller campaign, but I'm wondering if GURPS has published a system for mining that would give a table of ore availability and yield. The GM could just make it a long task and assign some arbitrary amount of ore available, but it would be fun to have a random ore generator, and a system to see how much prospectors retrieve after working for a set amount of hours.