A small handful of blocks added by UnEarthed use erroneous bottom textures when compared to similar vanilla blocks. They are as follows:

• Cut Siltstone and Chiselled Siltstone use their side texture on the bottom of the block, showing the side texture's upper border strangely. They should use their top texture, like cut/chiselled sandstone.
  

• Sandstone ores use their side texture on the bottom of the block, showing the side texture's upper border and making them look weird. They should use either the vanilla sandstone bottom texture, which doesn't have the border, or a new ore texture based on vanilla sandstone's bottom texture.
  

• Siltstone and siltstone ores technically have a similar issue, but the border is much harder to distinguish, so I wouldn't blame you for deeming this fine.
  

• Chiselled Beige Limestone uses its side texture on the bottom of the block, when the top texture might look better, but this is subjective.