The Green Monster Mineral Property is an eighty (80)-acre lode mining property located in the southern region of the Verde District, it has also been called the Verde Combination East Mine and the Silver Plate property. The assessment of this information is based on geographical mapping and historical accounts and descriptions.
The mine is named for the holding company from the early 1900s, known as Green Monster Mining. The Green Monster Mining company’s main holdings are 3-4 miles southeast of Jerome. The Green Monster Mine is slightly east of the main holdings and captures the apex of the Revenue Vein which the mine was developed on. The property produced bonanza values of 2.88 oz. AU and 187.88 oz AG to the ton. The gold valuations were taken from discarded dump material, which was higher in gold content but still averaged 15 oz. AG per ton.
The primary adit on the Verde Combination Mine is likely what was historically referred to as the Silver Plate Mine. This portal is the only horizontal access to the workings. The portal has been closed and walled in. Notice of Operations will need to be executed to access underground workings.
The underground workings are extensively developed and in good repair for the most part. There are multiple levels underground and the survey team fully mapped the main level. There is thought to be another level at 100 and 150’ below the main level. These levels accessed by internal shafts, winzes and large open stopes. There is some slough and collapse near the eastern edge of the workings which are thought to connect into the main shaft. This main shaft is known as the Cliff shaft and is part of a smaller holding of the Green Monster Mining Company.
The shaft is reported to be 903’ deep and bottoms into diorite, on the 500’ level the shaft met the crosscut which is thought to be the Silver Plate adit based on mapping and historical accounts. This 500’ level chased the “Revenue” vein. At 600’ there is a quartz porphyry containing chalcocite and chalcopyrite in a highly kaolinized leached zone.
The Green Monster is primarily a silver producing property with substantial gold values, there are surprisingly small copper values considering the region. The property sits just east of various patented properties which have never reported actual production. The Green Monster was cut under a fault line and produced many cars of ore that were processed at the base of the canyon near Cottonwood, AZ.
United Verde Copper reportedly took the property in 1960, where it was held as an asset and no work was completed. In 1980 they shuttered the mine, sealing the adit and the shaft as part of a good will reclamation effort. The mine was noted to have substantial reserves at that time, but metal prices were too low to profitably work them.
There is good road access to the portal of the mine. A short wheelbase 4-wheel drive vehicle and some technical skills will be required due to challenges on the trail. Most notably are off camber turns and washouts. It is recommended that as part of a notice of operation, the road be dozed and re-surfaced
There is a large platform that was used for winches and air compressors above the main shaft. These footings are consistent with the era of mining reported. The equipment was likely moved to another mine as there are no remnants of the headframe, or any of the machinery. It is always possible that the headframe and the machinery were pushed into the shaft and may be found at the base of the workings.
The roads to the site are well defined, and the route from the south is the only accessible path of access. 4WD is mandatory for steep and narrow roads with some off-camber sections. The road is open but has some technical portions. This has kept most vehicles and UTVs from accessing the site. Once at the claim, there is ample room for staging gear and machinery for processing.