Key points are not available for this paper at this time.
If heavy magnetic monopoles exist, then extreme magnetically charged black holes (P^2=M^2) with masses as small as 150 ({10^170ex{0ex}GeV) /}^2 g will be stable against evaporation over periods of 10^10 yr or longer, where is the mass of the lightest monopole. It appears unlikely that such black holes exist in the present universe, but this conclusion depends strongly on the details of the first 10^-24 sec of the universe. Such long-lived small holes will exist in the late universe if there is at least 1 monopole per 10^50 ({10^170ex{0ex}GeV) /}^6 baryons in the universe.
William A. Hiscock (1983) studied this question.