Calculations

Volume of a sphere:

V = \(\frac{4}{3} \pi r^3\)

V = \(\frac{1}{6} \pi d^3\)

Surface area of a sphere:

S = \(\pi d^2\)

Number of spheres per kilogram and per liter

Bead Diameter
Glass Density – see table below

Number of beads per kilogram
Weight of one bead
Average number of beads in 1 liter
Average weight of 1 liter

Density of selected glass types

Name	Density g/cm³	Name	Density g/cm³
Borosilicate (Simax)	2.23	Sal	2.39
Liba	2.58	Palex	2.45
K4 ŽBS	2.52	KS	2.49
B-glass	2.51	Unihost	2.49
Neutral	2.36	PN	2.61
F-2	3.61	MoKa	2.33
AR-Glas	2.52	Kovar	2.22
K1 – H	2.50	WoKa	2.38
ILLAX	2.50	LL	2.16
FIOLAX-clear	2.34	Fe-glass	3.16
FIOLAX-brown	2.42	FeCr-glass	3.25
K64 (21%Pb)	2.89	Mg-glass	2.52
K94 (32%Pb)	3.13	Pb-glass 24%	3.01
AWFT	2.46	Ba-glass	2.8
B-270	2.52	Multan	2.54
Eutal	2.57