Well, since you're already in so deep on this possible selenite, might as well read lots of books & feel lots of rocks to become THE top gem & mineral expert of the 21st century! Someone's got to do it! lol I'm laughing at myself, as I'm part of a multi-generational rock-hound family who've never learned much about what we're looking for until after we find it! Lots of fun anyhow. Pros don't always agree either, as I've found by taking some of my "mystery rock" finds to pros at my lapidary class and at quality gem & mineral shows. Whatever yours is, it's groovy! Andi