odd glass.

[bullshrink]

So I went out today to a large cornfield looking for arrow heads.my 4 year old daughter finds this palm size, purple, flat on one size, round on the other piece of glass.its chipped but smooth like sea glass. I also found this porcelain dolls head.on our walk out I saw a guy in the distance detecting so we went over to say hi.we ended up talking and he explain that the dolls head could be part of a doll traded with the Indians. What are your thoughts and any idea what the glass is?