Decanter?

I don't know much about this item. I bought it at a garage sale 10 years ago because I liked it. I think I only paid $2.00 maybe $5.00. I think it is handblown as there are no seams on it. This piece is darker toward the top and lightens as you get to the base.

I was curious if anyone could tell me where to start with my investigation as to maker, age, and possible value.

I appreciate any opinions or other help!