Silica

I recent viewing of the dust mentioned the dust was silica. I did note that another name of silica was Silicon dioxide. It is not clear to me what is the difference silicon is to silica/Silicon dioxide. However it is interesting what earthlings make with Silicon dioxide... *Glass/ceramics / Portland cement/ thermal protection fabric We see very little glass on this moon(Urns are the exception). What we do see of local production is water produced in the domes which many have assumed are some sort of atmosphere generator. I am just noting that there seems to be very little of natural resources on this moon used by the Engineers or any other race of being. Even with all of the tunnels mined out no natural resource is shown to be utilized. Strange. And even the water has been shown to the viewer why or even it's use. As humans we understand water's importantce to humans but not to the Engineer culture. In fact after the Last Engineer starts to move around he didn;t even ask for glass of water...or even where to find the nearest bathroom. Was it an Austin Powers movie that after a long sleep he visited the men's room for a looooong time? So the water's use still has not been explained. It just seems to me that a moon having silica storms that this site would have been selected for natural resources and for good reason. *