You call the bits of soil sediment.
Leftover material can be referred to as scraps, remnants, or remnants.
An organism's remnant or leftover is referred to as a fossil.
8 Bits is one Byte. Half of a byte (4 bits) is a nibble.
asteroids belt
Small leftover pieces of cigarette are called cigarette butts.
silt
Smaller rocks.
Datum
chicken mic bites
16 bits is a byte, for the record half a byte is called a "nibble". I kid you not...
Gold in small bits or powder is called gold dust.