Gathering data on CRT rebuild value

[eberts]

Leaving the tube open will degrade the aluminized coating on b&w tubes and the aluminum coating behind the phosphor on color tubes. Black matrix color tubes are even more sensitive.

It also depends on the temperature and humidity.
Black matrix color screens will get blotches on the screen within 48 hours on a hot, humid Ohio summer day. A non matrix screen will survive from 3 days to a week. A b&w aluminized tube will be garbage after 2 weeks.