My mother found some type of glowing green substance, what could it be?
So, yesterday night, my mom was gardening, and there's this one pot. It has dirt in it from before we moved in (5-6 years ago), and she started to dig it out. When she got around the bottom, she found these rocks, so she dug a bit further. THEN she found this glowing green stuff, it wasn't slimy, it felt like it was part of the rock. Remember, it was late at night. If it matters, we live in central Texas.
Any ideas on what it could be?