Common examples include: gypsum, quartz, plagioclase, staurolite Read more.

Common examples include: garnet, pyrite Read more.

Common examples include: fluorite, pyrite, galena, halite Read more.

Common examples include: hedenbergite, quartz Read more.

Common examples include: agate (and other chalcedony) Read more.

Common examples include: limonite, turquoise, cinnabar, quartz, realgar, lazurite Read more.

Common examples include: hemimorphite, elbaite Read more.

Common examples include: heulandite, subhedral zircon Amygdules or amygdales (/əˈmɪɡdjuːlz, -deɪlz/) form when the vesicles (pores from gas bubbles in lava) of a volcanic rock or other extrusive igneous rock are infilled with a secondary mineral, such as calcite, quartz, chlorite, or one of the zeolites. Amygdules usually… Read more.

Common examples include: stilbite Read more.

Common examples include: feldspar, topaz, vanadinite Read more.