Sure...there are many types of localized sand such as the black sands of Hawaii. That is composed of ground lava. Interesting stuff actually. There are also the singing sands of New Jersey and the hard packing sand that made racing possible on Daytona Beach.
The point was missed (probably due to my sarcasm). Stingrays live in the 'Silicone ' based sands that are present in every ocean. It does not bother them. Florida is composed of mostly sand in its entirety. The fresh water rays here do not get all scratched up either.
The first post in this thread is nearly verbatim of a sarcastic reply long ago. The only problem is that many people do not think critically and will repeat anything. Now the sarcastic post is being repeated like it is good advice.