Related Clues:

• Formality
• Bar rocks
• Witt's surface
• Diamonds, in mob lingo
• Chest contents, often
• It's sometimes sold in bags
• Rocks in a bar
• Drink cubes
• Venue for 6-Down
• Convenience store bagful
• It's hard to get a grip on
• Cooler contents
• Rocks, at the bar
• Gretzky's milieu
• Cooler for coolers