Question

A geologist determine that a sample of a mineral can’t be scratched by a steel naill but can be scratched by a Masonary drill bit. Based on this information, the sample mineral has to be softer than? A. fluorite B. Apatite C. Corundum D. Orthoclase

Answer 1

Answer:C

Explanation:Corundum is an extremely hard crystallized alumina, used as an abrasive. For example Ruby and sapphire

Corundum is extremely hard and it can scratch most minerals and than the drill bit of masonry that can smash the mineral sample.Which means mineral sample must be softer than corundum for this to be possible .

Therefore our answer is c

Answer 2

Answer:

C). Corundum

Explanation:

Corundum is a crystalline type of aluminum oxide that usually contains iron, titanium, vanadium and chromium traces. Corundum is an incredibly durable and hard material. It is the third hardest mineral, after moissanite and diamond.

A geologist determine that a sample of a mineral can’t be scratched by a steel naill but can be scratched by a Masonary drill bit. Based on this information, the sample mineral has to be softer than CORUNDUM.

Due to Corundum's hardness , it can scratch almost every other mineral, and Since corundum is harder than the drill bit of masonry that can smash the mineral sample and thus the mineral sample must be softer than corundum.