Commodity Code

corundum-gemstone

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

definition Corundum is the third hardest natural mineral known to science. The hardest mineral, diamond is still four times harder than corundum more like this
narrower ruby
broader corundum gemstone
sapphire
broader corundum gemstone
notation
01.03.07 more like this
CorGe more like this
source http://www.galleries.com/Corundum more like this
type
Resource
Concept
broader gemstones
narrower corundum gemstone
in scheme commodity code
is primary topic of corundum gemstone