I have been puzzling over this one for the last week, i have had a good look for something similar and drawn a blank, i think it's a creamer or it might be just a small vase, it has loads of wear to the outer surface of the glass body and heavy wear to the outer base rim and it does not weigh all that much, inside was black with dirt and worn, several white stones or seeds in the clear portion of the glass and a rough pontil.
5 inches in height and 2 1/4 inches across the base.
Any thoughts welcome regards Chris.