Commodity Code

pyrophyllite

http://resource.geosciml.org/classifier/cgi/commodity-code/pyrophyllite

definition A phyllosilicate mineral composed of aluminium silicate hydroxide: Al2Si4O10(OH)2. Pyrophyllite is easily machineable and has excellent thermal stability and is added to clay to reduce thermal expansion when firing and is combined with other compounds, such as in insecticide and for making bricks. It is also used for slate pencils, chalk (French chalk) and small carving. more like this
notation
01.02.01.03 more like this
Pphy more like this
source http://www.webmineral.com/data/Pyrophyllite.s html http://en.wikipedia.org/wiki/Pyrophyllite more like this
type
Resource
Concept
broader aluminosilicate
narrower pyrophyllite
in scheme commodity code
is primary topic of pyrophyllite