Gilded Blackstone

Gilded blackstone is a variant of blackstone that can drop itself or gold nuggets when mined.

Occurrence
Gilded blackstone can spawn in Bastion Remnants, in chests as well as in the structure itself.

From block loot
Gilded blackstone has a chance to drop gold nuggets when mined with any pickaxe, but Silk Touch is required to always obtain gilded blackstone in its block form.

Breaking
Gilded Blackstone requires a pickaxe to be mined, in which case it drops itself or gold nuggets. When mined without a pickaxe, it drops nothing. If Gilded Blackstone is mined with a Silk Touch enchanted pickaxe, it always drops itself. If it's mined with a Fortune III enchanted pickaxe, it always drops gold nuggets.

Block loot
Gilded blackstone has a 10% chance to drop 2-5 gold nuggets when mined with any pickaxe. If it does not drop golden nuggets, it will drop itself as a block. Fortune I increases the chance for this drop to 14.29% ($1/7$), Fortune II increases it to 25%, and Fortune III guarantees the golden nugget drop. If mined with Silk Touch, it will always drop itself.

Trivia

 * Gilded Blackstone is similar to gravel as it has a chance to drop itself or another item. The chances to get said item can be increased by mining it with a pickaxe enchanted with fortune.
 * Gilded Blackstone seems to combine the textures of unpolished Blackstone and the texture of Nether Gold Ore prior to its texture change.