it's impossible
you use a kitchen scale. there available in many places with cheap prices.
the rubies density is a 4 on the density scale
A kitchen scale
Mohs scale.
A kitchen scale is used for determining the weight of foods. For instance, if you are on a diet and need to precisely weigh 4 ounces of beef or other meat, a kitchen scale would help in determining that weight.
A kitchen scale
The Richter Scale is used to determine the earthquake density. The scale is measured from low as 1 to high as 10.
Moh's scale.
The Mohs Scale
In a kitchen scale.
on a kitchen scale
You weigh it on a kitchen scale.