useless trivia: What Word Means: A Wheel On Which Gems Are Ground Or Polished?

Questions

Fruit - Where is most of the vitamin C in fruits?

Fun Runs - What is San Francisco's equivalent to Sydney's 'City To Surf' race?

Furniture - What is the metal part of a lamp surrounding the bulb and supporting the shade called?

Furniture - Where did venetian blinds originate?

Games - How many dots are on a twister mat?