Feathered Postal Cards From Taiwan

Hello All,
I've been looking at a lot of postal stationery recently, but I think these postal cards from Taiwan (Republic of China) are the most unusual. I'm sure the artistic touch was added later. They are a mix of feathers and watercolor designs. I'm also sure they were not designed to travel through any form of postal machinery. They are still sealed in plastic covers for safety. There's no marks on them to let me know the artist(s). Anyone ever see these kinds before?
Will









And all of them have the same style of postal card - either mint or a favor cancel.

Wow!
always something new on SCF.
They are lovely, Will
Would sit alongside the embroidered postcards from Spain,
for beauty.
...and the collage postcards from China.

Yes, they are from Nantou City, Taiwan.But the pictures are not made by Post Office, they are private.