Revelation 21:19-20 (NIV) lists twelve kinds of precious stones that make up the city walls of the New Jerusalem: Jasper, Sapphire, Agate, Emerald, Onyx, Carnelian, Chrysolite, Beryl, Topaz, Chrysoprase, Jacinth, and Amethyst.
According to some Christian articles like The 12 Foundation Stones in New Jerusalem, these are all anisotropic gems.
I'm no expert in precious stones and a definitive list seems hard to find, but according to the article, 16 of 28 common gemstones are anisotropic, but that these weren't known until the last Century, around 1900 years after Revelation was written.
I think the naive odds that they would all be anisotropic are (16 choose 12) / (28 choose 12) which is about 1/16715. (The article suggests that the omission of common isotropic gems such as diamonds, makes it less likely than this.)
So, as best I can tell, if the facts are all correct, this either suggests:
The person who conceived of the city knew more about properties of precious stones than should have been possible in the 1st Century AD.
The author of Revelation "got lucky" (perhaps partly due to confirmation bias or other statistical fallacies).
There are perhaps more obvious properties that these gems have in common, that were known about at the time.
How good a case is there that the list of gemstones was revealed without information that was possible to know at the time?