Calculating rigidbody mass

Hey so im trying to realistically calculate the mass of a rigidbody

according o this post → What unit is Rigidbody Mass based on? - Unity Answers

a rigidbodys mass is the weight in kilograms

so lets just say i have a concrete slab 1 meter cubed that weighs 2400 kilograms

is the rigidbodys mass 2400 because i though mass is suppose to be a small number

Thanks ~Scott

Well the guy whose answer was accepted, linked an entry in the manual. That entry is no longer the same; it says it uses arbitrary units and not kilograms, unlike the scale of a mesh, which simulates meters.

Take a look at Unity - Manual: Rigidbody component reference , sections: Use the right size & Hints.