Descriptions

High quality, dark blue cobalt glass filter-not just blue glass like other low-cost alternatives. In flame tests, a mixture of sodium and potassium salts will produce an orange flame. This is because sodium's orange flame masks potassium's violet flame. If viewed through this filter, the orange color is blocked so that a violet-colored flame can be seen.

size: 50 x 50 x 3mm  (L x W x Thick)

pack of 10