As a whole, this is an unconvincing, scientifically inaccurate video whose overall point relies on speculation. For starters, most minerals exhibit anisotropic properties (the 12 listed aren't particularly special in any regard), which lends credence to the possibility that the jewels listed in Revelation are merely a coincidence. There's also the fact that cross-polarized light, in reality, is nothing at all like what the individual in the video claims it to be. When you lay two polarized lenses on top of each other at a right angle, you get zero light through at all. Cross-polarized light, as it turns out, uses one such polarized filter atop another, but the second is polarized in circles. The first kind is called a "linear" polarizer. And, to boot, you'd have to be wearing polarizing sunglasses or be fitted with eyes that can supposedly see such light interacting with certain minerals. There's also the fact that it's implied that rubies don't exhibit birefringency in the video, which is false.
"Very straight light" or "pure light" are terms that would probably be scoffed at by gemologists in reference to the anisotropic properties of gemstones.
