The World Silver Study 2012 in PDF provides a lot of meaningful information as far as source, mines output and uses...
An amazing fact I stumbled onto was that 1/2 of 2012's silver production came from no name miners... think about this if these no name miners failed because of production costs then the world's new silver production would drop by 50%.
Know personally geologists who analyze Satellite imagery searching for the world's mineral deposits... one result was a huge silver lode on a south american mountain top... upon physical investigation they discovered that beneath the dirt was a huge unknown glacier then the silver.
Totally unaccessible with today's mining technology.
To make this a short story there really isn't that much obtainable silver (at these market prices) in the world.
Someone on this Board (believe it was jon49trout who claims to be an engineer) once joked about x-raying the world... well believe because it has been.
Helpful but didn't give numbers. They did say 30 % went to Investment demand and mentioned 621 mil oz in Etf funds... WOW... If they really own that much is another WOW. No Audit allowed. But they said something that should alarm all and that is China jewelry usage is growing at Double digit growth . So is the Solar so Expect many problems for short supply in the future. Myself I am planning on buying more into Silver real soon.