These covers are not extracted from the ebook. Per
NiLuJe:
there's a slight 2px dropshadow on the bottom right corner when they've been generated on Kindle. Also, it is not the size of the cover (I will thus go back to my original 600x800). It seems to be related to the ASIN. Mobi to mobi conversion with calibre will insert a (fake) ASIN and once side loaded, the thumbnails would be generated by the Kindle. I can't check,
not having a touch.
Alternately
Gluggy's excellent Java Mobi Editor could be used to only insert a
EXTH 113 record with no further conversion (Which I will prefer if it works, since the conversion removed my "embedded" font).
Anyway,
could someone with a touch try the "cover view" and report with this Calibre converted ebook:
Klingon pIqaD Glyphs, Unicode, and Sound - PoP.mobi and with this ASIN-added-only ebook:
Klingon with ASIN.mobi