There is a bunch of people saying this kind of sand is better than that kind of sand..they even believe sand is made by crushing rocks. Sorry to be the bringer of the truth..SAND is not dangerous (unless you are buried to your neck in it and the tide comes in, or you are digging a tunnel in a mound of it or you decide to cram as much as you can down your throat. Fact 1: All quartz sand is silicon dioxide. If you see clear and colored but clear grains of sand, it's quartz. If you get dusty sand it has other minerals in it. Quartz is the most durable mineral commonly found Fact 2: Silica dust only happens if you deliberately pulverize to a flour consistency sand or quartz Fact 3: Silica is a term used properly by scientists and manufacturers and is most often found in electronics and opals in the real world. It is brandied about by idiots just like the word theory is. And just like asbestos, misunderstood, and therefore dangerous. Fact 4: Those publishing this garbage about sand ARE NOT GEOLOGISTS and do not know what they are talking about Fact 5: The washing of any sand does not make it safe or dangerous. Do you really think they would allow play sand for use in sand boxes for children to be sold if it had free silica dust in it? Fact 6: Sand is dredged up from rivers, gravel pits, and beaches, it is not made from crushing rocks. Fact 7: They wash all sand to get the organic debris out of it..Concrete would be worthless with a lot of rotting veggative matter mixed in it and play sand would stink as the organics rot and then so would children. This washing removes all the dust when done properly as well. The dust is usually from softer rock btw. I have written one person who has a popular website who quotes someone else who says play sand has silica in it (and based on that, used to say play sand was dangerous to animals)..people who do not know enough to understand what it is they are posting for others to read and believe need to be shut down. BTW, I have a degree in Geology...I have worked with many forms of silicon and washed much silicon dust down into the recovery bin.