While walking to the park, I found an empty deep blue bottle lying in the grass. The label said Bud Light Platinum, and was most likely filled with it, but the extra cost was for the deep blue bottle and clear plastic label. I took it back home and peeled the label off. This evening I looked through it at a string of Xmas tree lights with red, amber, green and blue LEDs in it. What I saw was not surprising, but interesting.
I could see the blue and green LEDs okay, but the amber and red LEDs were barely visible. The dark blue glass is acting as a narrow band filter, allowing only the colors that are close, such as blue and green, to get through. The longer wavelengths of red and amber are filtered out.