with speculative mining companies that are not in production (ie no income producing) do not fall into the 'insolvent' category. They are companies that are looking for finance continually, with large potential large revenue to come, if financed.
If not considering the above then about 1/2 of resource stocks a few hundred (ones not in production) are technically insolvent, and the ASX should investigate.
Matricks, you are probably an industrial sector investor, new to resources and is unsure how this sector works.