BH250-115
Title
BH250-115
Subject
Gneiss
Description
Major Minerals: quartz, biotite
Minor Minerals: plagioclase, hematite
Mineralogy Comments: biotite alteration
BH250-115 – Gneiss from Glacial Material near Northfield
This specimen is a gneiss collected from glacially transported material near Northfield. It displays a well-developed gneissose metamorphic fabric, characterized by distinct mineral banding and alignment of platy and elongate minerals. The texture reflects high-grade regional metamorphism, likely originating from deep crustal rocks before being incorporated into glacial deposits and transported to its present location.
Minor Minerals: plagioclase, hematite
Mineralogy Comments: biotite alteration
BH250-115 – Gneiss from Glacial Material near Northfield
This specimen is a gneiss collected from glacially transported material near Northfield. It displays a well-developed gneissose metamorphic fabric, characterized by distinct mineral banding and alignment of platy and elongate minerals. The texture reflects high-grade regional metamorphism, likely originating from deep crustal rocks before being incorporated into glacial deposits and transported to its present location.
Coverage
Location: Northfield, Minnesota, USA
Found in the Carleton Rock Garden
Found in the Carleton Rock Garden
Creator
Bereket Haileab
Source
From the rock collection of Bereket Haileab. Sample 115. Housed at Carleton College in Minnesota.
Type
Thin section and hand sample
Relation
Collection
Citation
Bereket Haileab, “BH250-115,” BH250 Mineralogy Teaching Collection, accessed April 25, 2026, https://bereket-haileab.geology.sites.carleton.edu/items/show/136.