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Silicate

Eastonite

KAlMg₂(Si₂Al₂)O₁₀(OH)₂
Crystal systemMonoclinic
ClassSilicate
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Eastonite specimen

Eastonite (Size: 3.5" x 2.5" x 2") Locality: C.K. Williams & Co. Quarry (Williams Quarry), Chestnut Hill, Easton, Forks Township, Northampton County, Pennsylvania, USA Flaky green eastonite — Photo: John Krygier · Public domain

Eastonite

Eastonite is an IMA-recognized mineral species in the silicate class, with the chemical formula KAlMg₂(Si₂Al₂)O₁₀(OH)₂.

It crystallizes in the monoclinic crystal system. It is a member of the Mica structural group.

IMA symbol Eas, IMA status: approved, named in 1925.

Index entry. This entry combines official IMA/RRUFF species data with published physical-property data — a full written entry hasn’t been published yet. Browse more E minerals or help write this entry.