Congratulations on finally obtaining your grail after 15 years of thinking of her 
It's sad to see her jacket didn't hold up well, but sadly not unex-pected
If the base of the fabric beneath the flaking silver top layer is still holding together as one piece (unlike Asuka's plugsuit did in Kanrabat's pictures ), I'd try to paint the fabric with silver acrylic paint. I have no clue if that'd work or how it would look with an uneven base and on such a relatively big area*, but that's something I thought of. Acyrlics are used on clothing items, so they do work on fabric.
*the suspenders of my J-doll Robson St's jeans dress are also made of faux leather and they started flaking immediately when they got wrinkled during redressing. I repainted the flaked-off area with white acrylic paint, and it looks perfectly fine, but that's a very small surface compared to Mercu's jacket...
It's sad to see her jacket didn't hold up well, but sadly not unex-pected
If the base of the fabric beneath the flaking silver top layer is still holding together as one piece (unlike Asuka's plugsuit did in Kanrabat's pictures ), I'd try to paint the fabric with silver acrylic paint. I have no clue if that'd work or how it would look with an uneven base and on such a relatively big area*, but that's something I thought of. Acyrlics are used on clothing items, so they do work on fabric.*the suspenders of my J-doll Robson St's jeans dress are also made of faux leather and they started flaking immediately when they got wrinkled during redressing. I repainted the flaked-off area with white acrylic paint, and it looks perfectly fine, but that's a very small surface compared to Mercu's jacket...
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"I wear my sunglasses at night
So I can, so I can
See the light that's right before my eyes"
"I wear my sunglasses at night
So I can, so I can
See the light that's right before my eyes"