Gilded Blackstone doesn't blend in with top texture

The Gilded Blackstone texture is based off of the side texture of Blackstone, which doesn't match the top. This means that Gilded Blackstone doesn't blend in with Blackstone when viewed from above or below, as it uses the same side texture all around. This can be fixed by having a different texture for the top and bottom, based off of Blackstone's top and bottom.