Tremolite is a member of the amphibole group in silicate minerals with the chemical formula of Ca2Mg5[(OH)Si4O11]2. The crystals are generally arranged in radial, fibrous or slender prismatic shapes.

Pargasite is a calcareous amphibole with the chemical formula NaCa2(Mg4 Al)(Si6 Al2)O22(OH)2, which can appear in different shades of green depending on the Fe content. Pargasite usually occurs in corundum as prisms, needles, and platelets.