Grandiderite

Named after naturalist Alfred Grandidier is an exceptionally rare gem typically found in Sri Lanka and Madagascar. Its rarity is due to the very specific conditions that need to occur in order for it to grow which happens when preexisting rocks are under immense heat and pressure to the point their chemical structure becomes unstable leading to minerals to break free, recombine with compatible minerals and recrystalize. In the case of grandiderite it is iron, magnesium, boron silicon an oxygen in which iron is the key component to its unique opaque mossy sea green. These are truley one of a kind gems

Hardness: 7 – 7.5
Composition: (Mg,Fe²⁺)Ai₃(BO₃)(SiO₄)O₂