Sand
Sand is the primary resource used for Glassblowing.
To learn how to mine for sand a GM Miner must read the book "Find Glass-Quality Sand". The ability does not cost any skill points, and has no effect on the skill cap.
The book can be bought from Gargoyle Alchemists and Stone Crafters in Ver Lor Reg, the Gargoyle city in Ilshenar. It costs about 10,000 gold and can only be read once.
Sand weighs 1 stone. Units dug up prior to Publish 56 cannot be stacked.
There appears to be roughly a 9% chance (9.04 to be more precise) to successfully dig up sand per attempt. The distribution of sand occurs in 8x8 resource grids that can be emptied out ("There is no sand here to mine"). Failing to dig up sand does not reduce the usages left on your mining tools.
You can expect 6-13 samples per resource grid area (8x8). Respawn times range from 10-20 minutes.