Do middle eastern sand dunes contain silicon dioxide (Silica, SiO2)?

Sand is purely a size classification of particles, not a composition. But a lot of common sand in deserts is mostly silica sand (quartz). 

Some of the quartz is fairly pure but not all - plus any scoop of loose sand you pick up is likely to have at least a few particles of some other mineral included.

So to mine sand for silica, first one would need to sort the silica sand (quartz) from the other material - this isn’t particularly difficult, but it isn’t extraordinarily simple, either.

However, there is no reason to expect sand dune silica sand to be any more difficult to manage than any other silica source. 

Generally any manufacturer wanting silica sand for processing is going to buy locally if possible because it is fairly heavy, so the transportation costs are important.

It may be easier to move a manufacturer close to your product, rather than move the product to a manufacturer.

https://www.quora.com/Do-middle-eastern-sand-dunes-contain-silicon-dioxide-Silica-SiO2