How about this report on the mine.
'BRIEF ASSESSMENT OF SANTA MARIA HOMESTAKE PROJECT
YAVAFAI COUNTY, ARIZONA, JAn. 1, 1993
By
GENE ENYART
LOCATION AND GEOLOGY
The property straddles the Santa Maria river starting about a mile west of Hwy 95 and extending southwest about two miles. Land surface is mostly between 1700 and 2500 feet above sea level. Temperatures range from below freezing to over 110 F in summer. It is arid. Plants include paloverde, creosote bush and cacti.
Outcropping rock is pre-Cambrian older than 1.5 billion years, and metamorphosed, consisting of granite, granit-gneisses, schists and quartzites, all extensively intruded by pegmatites. Relatively recently—in Mid-Miocene-tuff, ash and lava have covered the old rock and now have been eroded off again in large part, leaving "islands" of these young volcanics.
So far as I know now, gold mineralization is not significant in the volcanics here-although in this sane geologic province I have seen significant gold in the young rhyolites--and so the emphasis in evaluation will be on understanding the metamorphics.
Faults show that they have been subjected to early and late tension and to compression, and so relative movements include normal gravity slide and also nearly horizontal thrust displacement. (This keeps a geologist entertained) Mineralizing solutions rose on openings in fault systems often altering rock minerals adjacent.
In addition to quartz, these solutions deposited iron, lead, copper, silver and gold minerals. Sulfides were an important part in at least one mineralizing pulse and probably are cannon at depth in the fault systems. Mostly, near surface, the metallics, excepting gold and silver, are oxidized by meteoric waters reacting with sulfides. Dating of mineralization emplacement has not been done- The suite suggests at least three pulses. I suspect the latest was related to Miocene introduction of rhyolite. Two fault sets or more carry commercially significant ore.
Judging from mining history, two other consultant's reports and by spot checks in the vicinity of the SM-H mine, this kind of environment extends two miles westerly and a half mile wide. Vertical extent is not known, but the range in surface occurrence together with mining and drilling data indicate at least a thousand feet.
Mining has been confined to grades of about .4 to .8 opt. So far as we know now, shoots of such tenor are measured in tens and (less often) hundreds of feet in length along strike, widths of from a foot to a few feet and with vertical dimension tested little. Because such vein deposits typically are higher grade in shoots that rake at an angle down the fault plano, it is important to learn about the zoning, vertical extent and periodicity as veil as the usual tenor or the shoots.
If these same mineralized fault systems are looked at with a criterion for ore grade being set at .25 ort (or even as low as .05 orb for some widths) because of milling or mining innovations and market fluctuations, then the zones of interest are considerably enlarged. How they would appear we do not know, because they have not been explored or developed with such grades in mind. Nor have quite different systems, say stockworks, been sought.
Reserves in the immediate vicinity of the main shaft of the SM-H mine above the 150 root level and based on Sawyers Consultants samples are:
Assured 1850 tons with 580 oz (.31 opt)
Probable 1850 tons with 300+ oz (about .17 opt)
See Ore Blocks sketch
Results of sampling done by John Pierson for FMC corporation in 1987 and going to lover levels enlarge the picture.
Apart from a sample or ore in the chute (near where we are mining now) which ran .256 opt, and three samples selected on the hanging wall which assayed -188, 1.260 and .278 opt, the remaining 15 samples were across the vein and averaged .41 opt in.
With these data we can extend the calculation to the bottom level. They also have the effect of thickening the lower zone and raising the grade. (One sample in the shaft about 30 feet above the back of the lowest drift vas 10.1 feet or .996 opt.) Recalculating using these data:
Block 8 goes front 460 tons with 138 oz to 831 tons with 482 oz.
Block 9 goes from 548 tons with 164 oz to 839 tons with 355 oz.
Block 11 not calculated before has 1597 tons with 302 oz.
Block 12 not calculated before has 694k tons with 197 oz.
Block 4 would be somewhat higher in grade using Pierson's and my data.
Because these samples shift the "center of gravity" or mineralization to the southwest--agreeing much better with my theory of a shoot of high-grade raking down the fault plane--Block 10 is weakened and should be deleted in this calculation. That removes 1000 tons (possible) with 150 ounces. Overall the effect is an additional 1953 tons with 1084 OZS or a total of 5663 tans and 1977 oz (grade of .35 opt) about half of which may be, considered proved and half indicated.
Additional tonnage is indicated lower in the system and also to the northeast and southwest. It is undeveloped.
RESERVES IN P. M. Mining/Goldridge Inc. Area
Using data developed by Sawyer Consultants, Inc. and by John Pierson with FMC, I have made a first approximation of reserves in the area controlled by Don Blackburn and P. M. Mining/Goldridge, Inc. Claims cover about two square miles. The area considered for this calculation is about two miles long and a half-mile wide.
Although it is reasonably well explored it is far from developed, and so reserves are not veil-defined. Nevertheless, the hunter needs to decide whether it is appropriate to go ready for bear or carrying a 410.
At the SM-H mine, over a length of 800 feet surface samples do) averaged 2.2 feet at .189 opt. This is in an unfaulted part of the rein including the main shaft. Near the shaft over 5000 tons at .35 opt is partially developed. Possibly a like amount has teen removed, from a length measured along the fault of about 15C feet- Because sampling has indicated that this fault is mineralized generally and because high grade mineral exists at each end we may assume two more shoots similar to the one being mined, or 20,000 tons additional indicated reserves to 200 feet below surface.
East about 1400 feet from the E shaft5 a hill to; exhibits high-grade (.5 opt) float vein material. Southwest on a strike like that of the SM-H vein is an altered zone which assayed .095 opt over a width of 30 feet grab-sampled. Because these two occurrences are about 600 feet apart and one is high grade and presumably narrow while the other is of low grade and wide, it is difficult to assess. I think 6000 tons at .25 opt indicated can be safely assigned to it. There is the possibility here, as there is in two other known occurrences, for open pit low-grade.
Across the Santa Maria from the SM-H shaft is the Weepah mine. A small tonnage of high-grade has been shipped from it, but too little information is available now to permit estimatiing indicated ore.
Southwest of the SM-H mine are two shafts on the 3ig Stick vein, which probably is the same vein offset to the vest-in and near which mineral is consistent but mostly of low grade. Probably minable tonnage can be developed in this stretch, but it remains to be done.
On the south Big Stick vein segment samples over 130 feet averaged 2.4 feet at .773 opt. Extending this to 200 feet in depth and with mining width of 3 feet indicates 6000 tons at .62 opt (3720.02). In this same area an altered gneiss sampled over a width of 12 feet vent .127 opt. This suggests possible large tonnage of low-grade here.
We may use the 2nd level of the Waters nine as a sample of that vein because it is the largest test along that system One continuous shoot sampled over 150 feet averages 2-57 feet wide at .27 opt. A second, slightly offset by faulting is 90 feet long probably more when the faulting is understood correctly-and averages 3.8 feet wide at .207 opt. Together, and taken 500 feet down the vein, these would yield 27,954 tons with 6723 ounces (avg. .24 opt) indicated.
Summing up proved and indicated ore:
Location ……………………………. Tons ……………………. Ounces Au
Eastern SM-H …………………….. 6000 ………………………… 1500
SM-H near shaft (p) ……………… 3663 ………………………… 1977
east and west of shaft (I) …… 20,000 ………………………… 7000
South Big Stick ………………….. 6000 ………………………….. 3720
Waters (near river) ……………… 27,954 ……………………….. 6723
……………………………………………… 65,617 ……………………… 20,920 (.32 opt)
As can be seen on tile Veins, Faults and Workings map there is a considerable length or explored and partially developed vein system. It totals about 18,000 feet. About 10% of it has been developed to same extent. This provides one measure or undeveloped potential.
On these vein systems significant gold mineralization has been seen in surface shows, nine workings and drill holes over about 1000 feet vertically, and so I assume that generally deposition of gold here occurs over that range. It flay be more. For the purpose of estimating inferred ore known mineralization is projected over a total of 1000 feet measured along the dip of the system. This would always be less than 1000 feet vertical.
Location ………………… Tons ……… Ounces
Waters (near river) …….…….28,000 ……. 6,700
Eastern SM-H ………….…… 24,000 ……. 6,000
SM-H near shaft …….……... 22,650 ……. 7,900
E & W of ……………….…. 80,000 …….26,000
S. Big SE!Wk ………………. 24,000 …….14,880
Northern Waters …………… 36,000 …….23,400
Southern Waters …………... 50,000 …….11,600
SW of Big E ………………… 25,000 …….15,000
Other mineralized systems 20,0000 ……. 40,000
………………………………………… 509,650 ……. 143,480
END
143,480
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