Picked up an old used siphon sandblaster off Craigslist for relatively cheap. It came with 2 buckets of sand. The seller is a garage sale/auction reseller and claimed no knowledge of the blaster or media. I believe this is silica sand and if so won't use it except maybe outside in a strong wind and a respirator but if it's not sand I'll still use a respirator but try to reclaim it and re-use it. I'm not a sandblasting expert by any stretch of the imagination. Can any of you tell for sure if this is sand and not something safer? Thanks.