sey·bert·ite | \ ˈsībə(r)tˌīt\
Definition of seybertite
: a basic aluminosilicate Ca(Mg,Al)3(Al,Si)4(O,OH)12 of the clintonite group consisting of calcium, magnesium, and aluminum, occurring in monoclinic crystals and foliated masses and having a reddish brown, copper red, or yellowish color and submetallic luster (hardness 4–5, specific gravity 3–3.1)
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to mark by some ceremony or observation
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