What would happen if the gravity on earth decreases by a small about?

a loss of gravity on earth would  stop pulling down the air,water and earth's atmosphere

ther would be a sudden and significant loss of air pressure

the lack of any forceful gravitational pull would turn humans

Without gravity, humans and other objects would become weightless.

luster is not a good characteristic to use by itself because luster is the property of minerals that indicates how much the surface of a mineral reflects light. the luster of a mineral is affected by the brilliance of the light used to observe the mineral surface.