This round gold disc bears the date 1707, and purports to be an ingot from the Jesuit gold mines of Tubac, Arizona. But Tubac was only settled in 1752 (Weber 1993, 214). Its typology has no parallel with authentic coins, but much with the false Mexican gold bars. This led Buttrey to condemn the piece (Buttrey 1981). Hodder has described Buttrey's arguments condemning the ingot as “solid,” and refers to the ingot as “extremely problematical” (Hodder 1999, 94-95). The consensus is that the Tubac ingot is a forgery.
The Tubac ingot appears on a plate of the 1964 Encyclopedia Britannica with other questionable items - the Mexican gold bars and the USAOG items. John Ford supplied all these illustrations (Hodder 1999, 95).