For following tours visit sites where minerals can be studied and/or bought from local vendors:
The Trilobite's Sahara Kingdom - We visit the famous Filon 12 Mine that exist to mine mineral specimens to sell in rock shops around the world.
A Geological Safari - Namibia is famous for its minerals and many visited sites are mineral sites. There is also the opportunity to buy minerals from vendors.
Jurassic Coast, Wales & the Complete Geological Timescale - we visit the Brynteg mine where we can find our own specimens of chaclopyrite and galena.