Prehnite is a calcium aluminum silicate hydroxide mineral that forms in cavities within basaltic volcanic rocks, producing the distinctive pale green botryoidal (grape-like) clusters and translucent crystal aggregates that collectors prize. Our prehnite collection features specimens showcasing this mineral’s characteristic apple-green to yellow-green coloring and distinctive texture.
Named after Dutch Colonel Hendrik von Prehn — the first person to bring specimens to Europe from South Africa in 1788 — prehnite holds the distinction of being the first mineral named after a person. The mineral forms when calcium and aluminum-bearing fluids circulate through basalt vesicles and fractures, depositing prehnite alongside zeolite minerals. The resulting botryoidal or stalactitic formations often display excellent translucency, allowing light to penetrate and illuminate the crystal interior.
Notable prehnite localities include Mali (producing vivid green specimens), South Africa (the original discovery location), China, and India. At Mohs 6-6.5, prehnite is moderately hard and durable enough for standard display. The mineral’s soft green color and translucent quality make it visually distinctive among collector minerals. Browse our prehnite mineral specimens to add the gentle green of this historic calcium silicate to your collection.