buhrstone, also burrstone /bûrˈstōn/

1. A variety of quartz, containing many small empty cells, which give it a roughness of surface particularly adapted for millstones
2. A millstone made of this

• seat earth
• seated
• seater
• sea term
• sea terms
• seaters
• seating
• seatings
• seatless
• SEATO
• seat-of-the-pants
• seat rent
• sea trout
• sea trouts
• seats
• seat-stick
• seat-sticks
• sea turn
• sea turns
• sea turtle
• sea turtles
• sea unicorn
• sea unicorns
• sea urchin
• sea urchins