My presentation for the National Slate Association 2016 annual meeting
03/05/2016 2 Comments
Hello. This is my presentation for the National Slate Association (NSA) annual meeting, which was held in Philadelphia 3-6 march. I talked about some facts involving roofing slates:
– Definition of the petrological term slate versus the commercial and constructive term roofing slate.
– Types and characteristics of roofing slates
– Oxidation
-Carbonates
-Ribbons
-Roofing slate standards
About vcardenes
Roofing Slate 
Thank you very much Victor this is so informative. I am also trying to find out more about roofing slates for local residents. If your Octopus map a representation of naturally occurring slates available in different parts of the world? Or to show what is commercially available in this industry?
Either way thanks for such detailed info I will be checking back often. We get questions like this and it is good to have more information on it.
Hello Frank
The map represents most of the commercial varieties of roofing slates. There are areas, like Russia and China, that are continuosly improved, it is difficult to get info from these countries. The very small quarries and varieties are not represented, due to scale reasons. If you need info about local slate sources in the US, take a look to the US Geological Survey, they have a very good database of roofing slates (and other stones).
Cheers!.