Minecraft wiki entry for Beacon, associated text: The texture of the beacon is 16×16 but renders only the 10×10 area in the center.
It is possible to see the beacon beam on the bottom of an activated beacon. This was initially reported as a bug, but the resolution was "won't fix", despite a fix being provided.[2]
There are 12,326,391 different beam colors.
Despite it containing obsidian in its recipe, it does not need a diamond pickaxe to be mined.
A fully powered beacon can fit within the upper level of the Desert Temple with the beacon’s beam perfectly being placed in the hole at the top.