In the patch notes:
The following items can now be redeemed for company seals:
Item Type Seals Rank
Miniature Aetheryte Furnishing 14,470 Second Storm Lieutenant
Furnishing makes me think it's craftable, but I don't see it in any of the craft logs, nor on XIVDB. The new Savage Arc furnishing appears (GSM 2-star) though.

If the mini-aetheryte isn't craftable, how do you get it?