Definition of words:

1. Minerals with high color, luster, transparency and hardness can be used as decorations, bearings for instruments or abrasives.

2 refers to the kind of stone or mineral that can meet the requirements of jewelry after grinding and polishing.

3. Set with gems. -"Guangdong Military Affairs"

Precautions:

Jewelry:

Articles that have no practical value but are designed to increase aesthetic feeling.

Ore:

(1) contains useful minerals and rocks with mining value.

② In radio, it refers to galena and pyrite, which can be used as detectors.

Bearing:

A mechanical part used to support the shaft and bear the force transmitted by the shaft. According to the nature of friction, it can be divided into sliding bearing and rolling bearing. According to the bearing direction of the shaft, it is divided into radial bearing and thrust bearing.

Gloss:

Light reflected from the surface of an object: ruddy and shiny.