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

• bale-fire
• bale-fires
• baleful
• balefully
• balefulness
• balefulnesses
• bale out
• baler
• balers
• bales
• Balfour declaration
• balibuntal
• balibuntals
• Balinese
• baling
• balise
• balises
• balista
• balistae
• balistas
• balk
• Balkan
• Balkanisation
• Balkanise
• Balkanised