The Molly Marie Prospect is a group of 20 contiguous mining claims located in Maricopa County, Arizona. This website describes the exceptional geologic features of the Prospect that includes a very large, fully intact, IOCG (Iron Oxide Copper Gold) ore deposit located in a previously unrecognized submarine caldera over one mile in diameter.
Below is a photo showing the extents of the massive iron-oxide altered collapse breccias of the deposit on the west side of the caldera. There are very large gold-bearing quartz breccia pipes at the area labeled “Cerro Negra” that assay commonly .03 opt, and up to .04 opt gold. The quartz breccias are heavily malachite stained. The collapse breccias have assayed up to .06 opt Au. Assays of up to .05 Au, and silver up to 1.86 opt have been obtained in the basalt areas. Please note the highway located approximately 600 yards to the west of the caldera. The igneous rock exposed at the neck is an oxidized magnetic, brick-red, Rhyodacite porphyry.
Accompanying this deposit, located near the foot of the Superstition Mountains, is a subject that must be breached:
A “missing” mining district, The Peralta Mines.
The location of these legendary mines has commonly been thought to be deep inside the Superstition Wilderness area, but it’s just outside its boundaries. All of the stories told about lost mines in the Superstitions during the past 125 years have one thing in common; they do not have any geology to back them up, on a district scale. The geology of the District shown within proves the existence of the IOCG deposit, and proof that the District was mined by the Spanish and Mexicans (also shown within), demonstrates that the IOCG deposit is the most sought-after kind………. an exceptionally gold-rich one.
Proof that the Spanish and Mexicans mined the District also helps explain why a deposit so immense could go undiscovered; all of the most obvious outcrops indicating ore were simply removed and the pits (and shafts) were filled back in; intense alteration zones still betray their locations.
The root-cause of the richness of the deposit is likely the rock exposed at the volcanic neck: a pre-enriched porphyry. It is conceptualized that the volcano, the slope of which still partially remains (the eastern side), was the donor of the gold and copper for the orebody, which resulted in an IOCG of uncommon richness. The below photo shows what a portion of the volcanic neck looks like. The color of the porphyry betrays its high iron content.
The nearby Goldfield mining District, 2-1/2 miles away, has geologic features similar to that of the Molly Marie Prospect, including a caldera with breccias on its margin. Significant gold ore was mined there, in breccias, that assayed hundreds of ounces of gold to the ton; the volume of breccias at the Molly Marie caldera is multitudes greater than those at Goldfield (and contain much more iron).
Below is a silica mound that remains on the northeast portion of the prospect that “caps” a portion of the deposit.
Below is an exposure of silica beds on the south side of the north mound. All of this material is very magnetic.
Below is chrysocolla found at the base of the northern mound. There is chrysocolla scattered throughout the prospect. It is suspected that most chrysocolla was gathered on the property by prospectors in the 1960’s. A bathtub was found on the property that was commonly used for do-it-yourself heap leaching.
In the photo below, fossilized microbial mat can be see to the right of the barnacle. It is suggested that this life did not thrive around a black smoker or a white smoker, but a RED smoker, because of the large amount of hematite.
After 20 years of study and fieldwork, there is now enough evidence to present the mines that used to be, and where new mines could be.
Select any of the pages in the menu to begin……..
(cover photo is a view of the Superstition Mountains from the southern end of the Molly Marie Prospect)