Light transmision coeficients for some materials

Because we often use light that already passed trough different materials in the below table the informative values for light transmitting coeficients of theese are shown.

MATERIAL	TRANSMISION COEF (%)
China 3mm	3-8
White paper	40-50
White curtains (silk)	60-70
Ordinary double glass window	70-75
Transparent Plexiglass	70-80
Ornamental Glass	70-80
Painted Glass	70-80
Ordinary Glass	80
Crystal Glass	90
Quartz Glass	91-94

Its reccomanded, always verify the transformation that the light has suffered when passing trough differend materials.