Unusual Crystal Glass Votive Candle or Ashtray

This is an unusual old piece. It looks like a votive candle and I am sure can be used for that but it also has a dip in the edge for a cigarette or cigar, so it might be an ashtray. It has big irregular shaped glass hobnails all over the outside. It measures 2.5 inches tall and 3 inches across. It is unmarked and I don't know the maker. It is in excellent condition, no chips and no cracks and no cloudiness.