Message #51693

[hulagrub]

Alvin, I am a certified aggregate technician. To do a specific gravity for rocks, I have to submerse them in water for a minimum of 17 hours, then I dry the exterior of the rock and weigh it, then weigh it submerged in water. Then we put the rock in an 220 degree oven overnight, cool then weigh it again. Various calculations give you specific gravity, absorption rate and etc. that we use.
Specific gravity, is the weight of some thing in water as compared to what it weighs normally. This is why a piece of gold the size of a walnut, weighs more than the walnut.
Or density, is another way to look at it!