Onix Real Weight

okay now onix is listed @ 463.0 lbs. or 210.0 kg <-------
***assuming onix is composed of 15 rocks (that are spherical)
***with the first being 2 m, followed by rocks that are 1.9 m, 1.8 m, etc.
density of rock: http://www.lessonpaths.com/learn/i/rocks/densities-of-common-rocktypes
***unsure what kind of rock, so going with 2.5 g/m^3
density = 2.5 g/cm^3 ==> 2500 kg/m^3
volume = 4/3*pi*[(1)^3+(0.95)^3+(0.90)^3+(0.85)^3+(0.80)^3+(0.75)^3+(0.70)^3+(0.65)^3+(0.60)^3+(0.55)^3+(0.50)^3+(0.45)^3+(0.40)^3+(0.35)^3+(0.30)^3]
volume = 22.9728962794 m^3
density*volume = (2500 kg/m^3)*(22.9728962794 m^3)
mass = 57432.2406985 kg
weight = (57432.2406985 kg)*(2.2 lb/kg)/(2000 lb/ton)
weight = 63.18 tons <-- gf take physics pls