Browse Items (1651 total)

Hand Sample: Porphyritic orange-pink rhyolite. Dominantly potassium feldspar with some black crystals. Weathers to brown-black and yellow-brown.

Fine grained relatively soft calcareous sandstone. Thin Section Fine angular grains with fairly close packing characterize this thin section, with unusually sharp angles. Sample is still clay dominated.

Minerals found in the calcsilicate facies contain quartz, diopside, enstatitic pyroxene, tremolite, calcite, and phlogopite. However, only a few thin sections have been found to contain all phases. In some specimens, the pyroxene is close to 100%…

Includes sillimanite and K-spar

1:625000
includes Genesee river valley and early SUNY Geneseo campus

1:625000
includes Genesee river valley and early SUNY Geneseo campus

Fresh surfaces contain grey-white, anhedral calcite and dolomite crystals. Weathered surfaces are dark brown, with a fine powder observable after handling in hand sample. Bubbles from acid reaction turn dark brown on weathered surfaces. These…

Groundmass dominated by grey calcite and dolomite. Calcite and dolomite crystals are subhedral in thin section and hand sample.. (FOV: 1.28)

1:62500
Surveyed 1915-1916

1:62500
Surveyed 1915-1916

1:62500

1:62500

1:62500

1:62500

1:62500

1:62500

White Carbonatite. Found on Southwest side of the main rock unit body on North side of Beaver Creek about 1/4 mi.

Light brown to almost off-white fine grained Carbonatite. Delicated Barite appears in very thin layers on one side of the rock.

Iron rich Carbonatite.