This girl gave me a crystal, does it mean something?

The other night while out at a friends house in a sort of party like get-together this girl (one of my friends) came up to talk to me then before she went off I remembered she dropped something in my shirt pocket. I came across it later that night and was wondering why she would put some clear crystal in my pocket. I let someone look at it and lost it cause I really didn't care about a crystal. Then, the next night I was over at her house again, later in the night she walked up to me to grab something by me and said "take this", and it was another crystal. except this one is purple and white and rocky. I don't know if crystals mean anything to people I find this really weird to happen to me, (ahh crazy weekends). I don't know maybe she's crazy. but I was curious and found this website a href="http://www.newagedirectory.com/cry/amethyst.htm" rel="nofollow"http://www.newagedirectory.com/cry/ameth…/a