Consular cards were not designed to be identification and no treaty recognizes them as such. Legal travelers visitors and long-term residents carried passports visas or green cards for that purpose.
One of the consequences of the Iranian revolution has been an explosion of history. A country once known only from British consular reports and intrepid travelogues is now awash with historical documents letters diaries grainy video weblogs and secret police files of questionable authenticity.