A white fat cell fossil (Fig. 1), over 200 microns across- twice the
standard size of human fat cells, is found in meteorite NWA 5000. Fig.
1:
http://www.wretch.cc/album/show.php?i=lin440315&b=29&f=1782718851&p=25

Image source and credit for Fig. 1: http://www.meteorite.com/meteorite-gallery/meteorites-alpha_frame.htm
(Sourcing path: Select NWA 5000 article in the above URL, then scroll
down the right portion to the third photo)

Fig. 2: Terrestrial fat cells, labeled
http://www.wretch.cc/album/show.php?i=lin440315&b=28&f=1177279911&p=228
Image source and credit for Fig. 2:
http://www.anatomyatlases.org/MicroscopicAnatomy/Section03/Plate0340.shtml

Fig. 3: SEM of human white fat cells for comparison
http://www.visualsunlimited.com/image/I000007cTx6E7q.E