Two of the people accused of stealing a safe and $250,000 in silver coins and bars appeared in court Monday.
Renae Mason, 47, and 39-year old Giles Clark appeared via video from the Marshall County jail.
Both perpetrators are charged with theft, Clark is also charged with burglary.
Two other men are facing charges in the investigation, 37-year old Adam Beem and 38-year old Christopher Mason.
The men are accused of stealing a safe from a Marshalltown building then cashing in the coins and silver bars they found inside.
Authorities are working to recover the stolen silver and the profits the men earned from selling it.