H-c1 and H-c2 were accurately estimated in U6Fe by ac susceptibility.
T-c and two anomalies were found at 4.10, 3.7 and 2.7 K, respectively.
H-c1 was analyzed by Bean's model and found to be 0.13 T at T = 0 K,
which is an order of magnitude larger than that obtained by SQUID with
a residual field and field distribution of the SQUID meter. H-c2 is 6
T at 0 K.