DetailsBlue aventurine tumblestones, tumbled and polished to give them a brighter appearance and make them smooth to handle. Blue aventurine is a variation of aventurine and in turn a variation of quartz, sharing the conchoidal fracture seen in glassy minerals. It is blue due to the presence of chrome bearing fuchsite mica during its formation. This fuchsite can also make aventurine appear green. The pieces range in size between 2 to 3 cm and are available as a single gemstone or in sets.