I have yet to see any evidence that cannabis even uptakes silicon, but I have not been looking for any studies simply because I could never tell any difference in anything if I used it or didnt use it. Most monocots and members of Pinaceae will readily uptake it but a lot of the broadleafs dont, alot of them exclude it at the root. It can cause microscopic "glass" particles in seed of some of the monocots that can cause esophageal cancer when eaten, dont know about burning IF they were in your hash or flower.