I doubt it is sand. Was it white and crusty around the nostrils? If so they get this from time to time, just excess salt build up, lizards expell the excess salt from their bodys , usually by sneezing out through the nose. Many times you will see white splatters on the tank sides. See it more with bigger lizards but they all do it. We call this SNALT..... lol sneeze salt/snalt

If the nostrils seem clogged with the white crust, you can take a q-tip with warmish water and dab it off or should clear up by it self in a few days.

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Eve
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