Skip to main content
  • Utility Menu
  • Search
Harvard Logo
HARVARD.EDU

Mineralogical & Geological Museum

  • HOME
  • Collections
    • Areas of the Collection
      • Mineral and Gem Collection
      • Rock and Ore Collecion
      • Meteorite Collection
      • EPS Teaching Collection
    • Request Material
      • Analytical Sampling
      • Image Requests
      • Loan Requests
    • Search the Collection
  • Exhibitions
  • Give
  • People
  • About
    • History
    • Careers
    • Frequently Asked Questions
Collections Menu
  • Collections
  • Categories
  • Exhibitions
  • Geography
  • Shared My Collections
  • About
  • Advanced Search
  • Sign on
Advanced Search
  • Home
  • Works
  • Images (3)

Fused Granodiorite

  • Images (3)

Fused Granodiorite

Field Collector: Esper Signius Larsen Jr.

Place Collected:Cerro de la Calavera, San Luis Rey Quadrangle, California
Object number: ROC21715
DescriptionPorphyritic igneous rock that is black with anhedral white plagioclase phenocrysts. This rock consists of 70% black groundmass composed of black glass and 30% off-white plagioclase phenocrysts. This rock is thought to have formed from the melting of a granodiorite under very ideal conditions, it was already close to the surface (cool) when encompased by an andesite intrusion, and there was a lot of water involved according to Larsen and Switzer (1939).
In Collection(s)
  • Larsen Southern California

Choose Collection

Create new collection
  • Privacy Statement
  • Rights and Permissions
Admin Login
OpenScholar
Copyright © 2017 The President and Fellows of Harvard College | Accessibility | Report Copyright Infringement

Choose Collection

Create new collection