Question

Silica crystals of different size embedded on paper is called:

• A. emery paper
• B. sand paper
• C. rough paper
• D. grinding paper

Answer 1

Answer: (A), (B)

The correct options are
A emery paper
B sand paper

Emery paper is a type of abrasive paper or sandpaper, that can be used to abrade (remove material from) surfaces or mechanically finish a surface. Operations include deburring, polishing, paint removal, corrosion removal, sizing, etc.

Originally, emery paper was made from milled emery rock, bonded or sized to paper often with an animal glue for water resistance. Today, synthetic adhesives are used in place of natural glues and silicon carbide is often substituted for emery. Silicon carbide being slightly harder, and more durable with less tendency to fracture than corundum. The use of emery papers is rare today generally being replaced with silicon carbide papers.