Falcondoite and willemseite are rare nickel, magnesium silicates found in a serpentinized harzbergite massif or an obducted ophiolite at a plate collision of oceanic crust with continental crust. The locality is in the Dominican Republic, which is the Type Locality for falcondoite. This very showy, bright green thin crust is mostly green falcondoite, with just a bit of lighter, olive willemseite.