Browse Items (1651 total)

1:62500

1:62500

Relics of augitic clinopyroxene, albite, actinolite, chlorite, clinozoisite, and sphene. Relics of the clinopyroxene of the original dolerite are in part substituted by chlorite and actinolite in a granoblastic and metablastic matrix of albite,…

OCR PDF of supplemental information for the Powderhorn Carbonatite collection.

1:24000

1:24000
includes Genesee River and town of Portageville.
one is mounted on board

1:24000

1:24000
includes Genesee River and town of Portageville.
one is mounted on board

1:62500

1:62500

1:62500

1:62500

Macroscopic: Porphyroblastic staurolite, andalusite, cordierite, garnet, biotite, chlorite, muscovite schist. Cross bedding or graded bedding may be apparent in some samples. Mineral zone: staurolite-andalusite. Microscopic: Large garnet phenocrysts…

The porphyroblastic metasediments/hybrid rocks were interpreted by Eales and his co-workers to be metamorphosed "Red Beds" Formation sediments but could be magmatic in origin. The samples illustrate the range in textures; see KBR 12 and KBR 13 to…

The porphyroblastic metasediments/hybrid rocks were interpreted by Eales and his co-workers to be metamorphosed "Red Beds" Formation sediments but could be magmatic in origin. The samples illustrate the range in textures; see KBR 12 and KBR 14 to…

The porphyroblastic metasediments/hybrid rocks were interpreted by Eales and his co-workers to be metamorphosed "Red Beds" Formation sediments but could be magmatic in origin. The samples illustrate the range in textures; see KBR 13 and KBR 14 to…

Macroscopic: Mega-porphyroblastic andalusite, cordierite, staurolite, biotite, garnet schist. Relict bedding, cross bedding or graded bedding may be apparent in some samples. Mineral zone: staurolite-andalusite. Microscopic: Large garnet phenocrysts…

Fenitized porphyroblastic Gneiss.

Hand Sample:

Entirely coarse-grained rock except for 2 cm wide dark fine grained band. Obvious traces of oxidation appear on all sides, dominating the most weathered sides of the rock.

Quartz and feldspar phenocrysts, rounded diabase inclusions

Contains orthoclase, ligoclase, and quartz phenocrysts and has alterations of kaolinite, sericite, and epidote