This is a listing of trace impurities in some of our coverslips and slides.

Trace Impurities

Element	Electrically Fused Tubing & Rod	Electrically Fused Ingot	Flame Fused Ingot	Fused Silica Flame Fused
Ag	—	—	—	<2ppm
Al	14ppm	14ppm	15ppm	<25ppm
As	<.002ppm	<.002ppm	—	<15ppm
Au	—	—	—	<1ppm
B	<0.2ppm	<0.2ppm	—	<10ppm
Ba	—	—	—	<1ppm
Be	—	—	—	<0.5ppm
Bi	—	—	—	<0ppm
Ca	0.4ppm	0.4ppm	0.5ppm	<15ppm
Cd	<0.01ppm	<0.01ppm	—	<0.3ppm
Co	—	—	—	<0.5ppm
Cr	<0.05ppm	0.05ppm	<0.01	<1ppm
Cu	<0.05ppm	<0.05ppm	<0.01	<2ppm
Fe	0.2ppm	0.2ppm	0.1ppm	<20ppm
Ga	—	—	—	<0.5ppm
K	0.6ppm	0.6ppm	0.2ppm	<5ppm
Li	0.6ppm	0.6ppm	0.2ppm	<7.2ppm
Mg	0.1ppm	0.1ppm	—	<5ppm
Mn	<0.05ppm	<0.05ppm	0.01ppm	<1ppm
Mo	—	—	—	<1ppm
Na	0.7ppm	0.7ppm	0.1ppm	<187ppm
Nd	—	—	0.1ppm	—
Ni	<0.1ppm	<0.1ppm	—	<5ppm
P	<0.2ppm	<0.2ppm	—	<50ppm
Sb	<0.003ppm	<0.003ppm	—	<0.5ppm
Sr	—	—	—	<0.5ppm
Th	—	—	—	<0.5ppm
Ti	1.1ppm	1.1ppm	1.3ppm	<10ppm
U	—	—	—	<1ppm
V	—	—	—	<1ppm
Y	—	—	<0.1ppm	—
Zn	—	—	—	<5ppm
Zr	0.8ppm	0.8	1.3ppm	<5ppm
OH	<5ppm	<5ppm	170ppm	<1000ppm

Coverslip and Slide Trace Impurities