I bought a few 50lb bags of the of black 3M Spectraquartz sand and never ended up using them all. It's super fish safe and a way cheaper alternative to the Tahitian Moon Sand for tanks where you want a fine black substrate.
This stuff is great - we never used these bags so they are unopened. I also have a small 2g bucket of the red 3M sand if you want a different color.
Review here from a fishkeeper: https://www.aquariumadvice.com/forum...ew-214492.html