You know EU, I was looking up Aventurine and wondering if that's what it really is? It's just looks so different in a way. Is Mica (Fuchsite) soft? This is very hard. I've seen some white rock that looks like mica, no green yet.
First you have elements, things like silicon and oxygen.
Then you have minerals which are combinations of elements, like silicon dioxide, better known as quartz.
Then you get rocks which are combinations of minerals. Then those rocks change.
Then people call those rocks by different names because of where they live.
Then people change the name on e-bay because they want to confuse you.