Rock Crossword

having solidified from lava or magma
exhibiting structural change
that has formed from sediment deposited by water or air
a combustible black or dark brown rock consisting chiefly of carbonised plant matter, found mainly in underground seams and used as fuel
a speckled, coarse-grained igneous rock consisting essentially of plagioclase, feldspar, and hornblende or other mafic minerals.
a very hard, granular, crystalline, igneous rock consisting mainly of quartz, mica, and feldspar and often used as a building stone
a dark, fine-grained, brown or greyish intermediate volcanic rock which is a common constituent of lava's in some areas.
a dark fine-grained volcanic rock that sometimes displays a columnar structure, typically composed largely of plagioclase with pyroxene and olivine
a sediment or sedimentary rock composed of very fine clay or mud particles.
a hard-sedimentary rock, composed mainly of calcium carbonate or dolomite, used as building material and in the making of cement
an extremely compact, hard, granular rock consisting essentially of quartz. It often occurs as silicified sandstone, as in sarsen stones
a dark, fine-grained metamorphic rock consisting largely of quartz, mica, and feldspars.
a metamorphic rock containing granular minerals, typically garnet and pyroxene.
a hard, dark, glasslike volcanic rock formed by the rapid solidification of lava without crystallization
an altered igneous rock that is usually opaque with green, black, pink, and white flecks and is usually used as a gemstone
a light, porous rock formed by consolidation of volcanic ash
a pale fine-grained volcanic rock of granitic composition, typically porphyritic in texture.
a hard, dense, fine-grained siliceous rock resembling chert, with a high content of microcrystalline quartz.