Amethyst Depth

I noticed an interesting pattern with ores in Minecraft: As you go deeper, ores gradually appear brighter and brighter in color. This is important because we percieve bright and colorful objects as more eye-catching and tend to apply more significance to them as a result. Based on this logic, since it requires effort for the player to descend the depths of the world, it makes sense to reward them with brighter and rarer ores. With that said, I thought that it was a bit jarring that amethyst generated near the surface of the world. Naturally, you would only see the dull blacks and browns of coal and iron at the surface, so the bright purple of the amethyst didn't seem to fit the theme of "More depth = More colorful (and thus more desirable) materials". A suggestion of where to put the amethyst would be to have it start generating around the same depth as other colorful ores (i.e. gold and lapis lazuli).