```\nfunction pauseCollateralType(\n    address _collateralAddress,\n    bytes32 _currencyKey\n    ) external collateralExists(_collateralAddress) onlyAdmin {\n    require(_collateralAddress != address(0)); //this should get caught by the collateralExists check but just to be careful\n    //checks two inputs to help prevent input mistakes\n    require( _currencyKey == collateralProps[_collateralAddress].currencyKey, "Mismatched data");\n    collateralValid[_collateralAddress] = false;\n    collateralPaused[_collateralAddress] = true;\n}\n```\n