Tourmaline Aplite (#501)
 >View Microscope
 >View Object
Fact sheet
Description: 

This unusual rock type shows the remarkable replacative capability of boron-rich magmatic fluids. Original white orthoclase feldspar phenocrysts have been totally replaced by black tourmaline. Note the original zoning of the orthoclase that is visible in hand specimen.

In Place
In Time
Location description: 
Wheal Martyn china clay pit, Carthew, near St Austell
Accuracy:
Location precision: 
Moderate
Timescale:
Timescale: 
Permian
Ma = Millions of years ago
In Focus
Collection:
What\
Type:
Type: 
igneous
What\
Rock-forming minerals:

Rock forming mineral:

What\