Cobalt Uranyl Acetate

["William Kolb" <William_Kolb_at_SETA@mail.hq.faa.gov>]

At a recent outing to an antique scientific instruments show, I saw a laboratory 
balance that had some slide preparation materials in its drawer. There was also 
a 10 gm vial of cobalt uranyl acetate.  A quick reading made with a 2" pancake 
tube suggests that depleted uranium was used.  I've checked a 40s vintage CRC 
and a 30s vintage Merck Index for this compound to no avail.  Can anyone tell me 
what the formula was and what this material might have been used for?  

bill kolb
ARINC Research Corp.
bkolb@arinc.com