What would human ashes lol like? Example: sand, gravel, powder?

More like dust with larger pieces mixed in.

Why?

Hi why1,
When a person is cremated all the organic matter is burned away leaving only the bones. Then the bones are placed in a pulverizer that crushes the bones into small uniform fragments. The age and type of the pulverizer, the length of time the bones are left in there to grind, the amount of bone, and it's density (an infant or child vs. a large boned adult) will determine the appearance and the amount of cremains. They can appear like fine sand to crushed sea shells. The less dense the bones and the longer in the pulverizer will make for a more sand-like appearance.
So again, the variation in appearance has to do with bone density and quantity, the type and age of machinery, and time in the machine (which is up to the discretion of the person at the crematory). I hope this is helpful. As you can see there are some variables that would account for the differences in appearance of cremains.

thamk u for asking this question I wonderede myself my dads ashes sound like sea shells :-(