vintage hand blown glass tumblers, blue & white swirl slag glass vases or drinking glasses

Set of six vintage hand blown glass tumblers in blue and white slag glass... love that beautiful blue color, like a blue sky with clouds.

These are slightly uneven in size and form (a couple of these stand crooked) and have bubbles and dark inclusions in the glass itself. I think probably Mexican art glass, 80s or 90s vintage?

They're about 5 1/4" to 5 1/2" tall. The interiors and rims look very good, you could use these as drinking glasses. Or as individual place setting vases!