Commodity Code

slate

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

definition Commercial slate is a microgranular metamorphic rock formed by the recrystallization of clay sediments, such as claystone, shale, or siltstone. Characterized by excellent parallel cleavage, slates may be easily split into relatively thin slabs. more like this
notation
01.01.03.08 more like this
Slt more like this
source http://minerals.usgs.gov/minerals/pubs/commodity/stone_dimension/myb1-2007-stond.pdf more like this
type
Resource
Concept
broader dimension stone
narrower slate
in scheme commodity code
is primary topic of slate