About
Rio Grande holds an option to earn a 100% interest in both the Ivanhoe and Emporia past producing gold-silver mines, which consist of two patented mining claims. The main shaft reaches a depth of 384 feet, with a 370-foot decline. There is potential for large tonnages of lower grade stockwork veins surrounding the historically mined high grade veins. Soil geochemistry and geophysical anomalies have been defined for follow-up, as favorable structural conditions persist along the bends and jogs of the Paymaster Fault— a structural trend known for historic gold deposits.
Photo 1 – Displays Ivanhoe Mine, surface vein trace indicated by red line and blue squares show adits.
Past preparatory work for drilling has included data compilation of historical and recent data, along with acquisition of high-resolution LiDAR satellite imagery to constructan accurate terrain model. This was followed by geophysical surveys using both electrical and magnetic methods. |
Exploration
Historic exploration and drilling at Ivanhoe and Emporia
Historical mining in most cases ceased due to the decline in the historical price of silver and gold. Most records relating to the estimated grades and/or tonnages of the Ivanhoe Claim and mine are similar to those stated in independent reports between 1940 and 1989 found for the adjoining Emporia mine. This includes the high quality of raw data, but also the lack of specific locations and detailed calculations of the reported mineralization. Freeman, (1986, 1989) provides more detailed calculations regarding the mineralization present.
Previously, three) samples were collected from piles of quartz dump material near the mouth of the mine, excavated in the early 1980’s. Two of these composite samples, representative of the main style of quartz present, returned assay values of 179 g/t Ag and 2.9 g/t Au and 170 g/t Ag and 6.7 g/t. Au. A third composite sample of fine-grained grey “cherty” quartz material found on one of the dumps returned values of 1,439 g/t Ag and 25.2 g/t Au
All historical reports of resources and reserves, including statements of grades associated with sampling, production, tonnages, widths, and lengths, do not meet NI 43-101 standards and should not be relied upon.
Historic data of the exploration targets as summarized in Table 1.
Table 1 – Exploration target for combined Emporia and Ivanhoe Mines, Sierra County, New Mexico (based on Entwhistle, 1944; Entwhistle, 1948; Ristorcelli, 1980; Freeman, 1986; and Freeman, 1989).
| MINE | EXPL TGT SIZE (tons) | AU (opt) | AG (opt) | AU + AG | BASIS OF ESTIMATE | REFERENCE |
|---|---|---|---|---|---|---|
| Emporia & Ivanhoe | 8,704 to 350,000 | 0.146 to 0.248 | 4.46 to 15.75 | NR | 7 composite bulk dump samples from 64 pits | Daffron (1978) |
| Emporia & Ivanhoe | 191,000 to 350,000 | 0.005 to 2.470 | 1.93 to 39.00 | NR | 18 channel samples + 22 channel samples | Lemback (1978), Ristorcelli (1980) |
| Emporia & Ivanhoe | 16,566 to 121,066 | 0.055 to 0.056 | 6.23 to 7.77 | NR | 94 channel samples + 55 channel samples | Freeman (1986), Freeman (1989) |
Current exploration at Ivanhoe and Emporia
The property is at an early stage of exploration with most recent work conducted by Foremost Clean Energy. This includes reconnaissance mapping, rock chip sampling, 32-line-kilometers of ground magnetometer surveys, and LiDAR terrain model analysis. The primary focus was on determining the structural controls of the silver-gold mineralization. Samples were collected to better understand the vertical expression of the epithermal system, identify the precious metal horizon, and define the areas of greatest economic interest. Sample results at the Ivanhoe and Emporia are outlined in Table 2 below.
Table 2
| SAMPLE # | COMMENT | MINE | G/T GOLD | G/T SILVER |
|---|---|---|---|---|
| 1670958 | Sugary white quartz w patches of black sulphides | Emporia | 46.10 | 366.0 |
| 1670959 | Amethyst vein and breccia w minor oxides | Emporia | 0.02 | 1.0 |
| 1670960 | Banded vein w some red zones and minor ginguro | Emporia | 44.90 | 517.0 |
| 1670957 | Banded comb quartz w calcite, oxides, dark gray zones | Ivanhoe | 0.38 | 563.0 |
| 1670976 | Sugary quartz/adularia/calcite banded vein w black sulphide bands, up to 20% locally | Ivanhoe | 4.82 | 1,670.0 |
| 1670977 | Layered comb amethyst w oxides and replacement textures | Ivanhoe | 0.02 | 3.8 |
| 1670978 | Massive dark gray quartz w red oxide zone, some copper oxide | Ivanhoe | 2.91 | 628.0 |
| 1670979 | Calcite breccia w chalcopyrite, included banded vein clast | Ivanhoe | 0.47 | 383.0 |
| 1670980 | Layered chalcedony w black sulphide, minor calcite | Ivanhoe | 26.80 | 940.0 |
| 1670981 | Qtz/adularia vein w green mustard oxide | Ivanhoe | 1.30 | 849.0 |
This property has seen little to no modern exploration since the early 1980’s. With such high-grade samples being returned, the investment community is eager to see drill results and unlock the full potential from the Winston Gold/Silver project, which has yet to be realized.
*The estimated potential of the quantity and grade of the mineralization listed above is conceptual in nature and there has been insufficient exploration to define a mineral resource using NI 43-101 guidelines. Additionally, it is uncertain if further exploration will result in the targets being delineated as a mineral resource. The expressed potential of the targets is based on the results of extensive historical underground channel sampling and bulk sampling of surface dumps.
