Amethyst amplifying enchanting

When you put bookshelves around an enchant table, you can get higher level enchants. But what if you could do something similar with amethyst? By placing amethyst clusters (obtained by silk touch) around you enchant table, you could get a higher chance of getting multiple enchants at a time. Ex: if you had 0 amethyst around your enchant table, getting multiple enchants from one enchantment is still relatively rare. If you had 8 amethyst around your table, you could have a 55% chance of getting multiple enchants from one level 30 enchant. I think this could make amethyst more useful without making them too OP.