How big is a Quant?

I did read the tutorial and tried to understand several times how big a quant is but i don't get it. Lets say I have in my hand a pencil that is 6cm long. Now I want to add this pencil to my 3d world with the exact measure. How many quants would 6cm be? How many quants is 1cm?

check here. Please use the search feature before posting. This was on the first page of the faqs forum.

ok thanks