Glass ribbed bowl

Translucent pale streaky purple; trail in opaque white.
Knocked-off, uneven rim; short concave neck; squat globular body curving in to flat, thick bottom.
Trail wound spirally around body, with large circular patch on bottom, ending in a fine trail on shoulder; side tooled into twenty-three irregular, vertical ribs.
Intact, except for large chip in rim; some bubbles and a few gritty inclusions; dulling, faint iridescence and weathering, and pitting of broad trail around lower body.

Reddish amethyst bowl with white wavy lines and bottom.