triplite

{{Infobox mineral | name = Triplite | category = Phosphate minerals | image = Triplite-t5105a.jpg | imagesize = | caption = Triplite from Alchuri, Shigar Valley, Baltistan, Pakistan (1.2 × 1 × 0.9 cm) | formula = (Mn,Fe)2(PO4)(F,OH) | IMAsymbol = Trl | molweight = | strunz = 8.BB.10 | system = Monoclinic | class = Prismatic (2/m) (same H-M symbol) | symmetry = I2/a (no. 15) | unit cell = a = 11.97 Å, b = 6.52 Å c = 10.09 Å; β = 105.62°; Z = 8 | color = Chestnut to reddish brown, flesh-red, salmon-pink | habit = Prismatic, massive to nodular | twinning = | cleavage = Good on {001}, fair on {010}, poor on {100} | fracture = Uneven to subconchoidal | mohs = 5 to 5.5 | luster = Vitreous to resinous | refractive = nα=1.643–1.684, nβ=1.647–1.693, nγ=1.668–1.703 | opticalprop = Biaxial (+) | 2V = 25 – 76° | dispersion = r > v, moderate to strong | birefringence = | pleochroism = Distinct; yellow-brown to reddish brown | streak = White to brown | gravity = 3.5 – 3.9 | density = | melt = | fusibility = | diagnostic = | solubility = | diaphaneity = Translucent to opaque | alteration = Alters to brownish black | other = | references = }}

Triplite is a rare phosphate mineral with formula: . It occurs in phosphate-rich granitic pegmatites typically as irregular brown opaque masses. Triplite was first described in 1813 for an occurrence in Chanteloube, Limousin, France. The name is from the Greek triplos for triple, in reference to the three cleavage directions. In color and appearance, it is very similar to rhodocrosite, another manganese bearing mineral. Chemically, it is also quite similar to triploidite the difference being that triplite is fluorine dominant while triploidite is hydroxide dominant.