اسکارن

Also known as tactite

thumb|Microscopic view of skarn under crossed polarizers thumb|Hand sample of skarn containing serpentinite from the edge of the Alta Stock, [[Little Cottonwood Canyon, Utah]] Skarns or tactites are coarse-grained metamorphic rocks that form by replacement of carbonate-bearing rocks during regional or contact metamorphism and metasomatism. Skarns may form by metamorphic recrystallization of impure carbonate protoliths, bimetasomatic reaction of different lithologies, and infiltration metasomatism by magmatic-hydrothermal fluids. Skarns tend to be rich in calcium-magnesium-iron-manganese-alumin