Up to this point, it seems likely that prospecting had been guided by reports from mountain men such as William Graham and James Stuart, who had visited the area in the 1850's. Now the element of pure good luck enters the picture. According to Rossiter Raymond, a party of prospectors on their way from Idaho to the Blackfoot gold diggings (actually in the Little Blackfoot drainage near Elliston) staked many of the best silver showings beginning with the Comanche lode (July 4). As best we can reconstruct the record, this group consisted of Dan Brown, Dan's brother Sandy (Emanuel), Charles Frost, Ben Franklin, John Edwards, Dan Chisholm, Wm. Mathias, C.A. Bell, and perhaps several others. Rossiter Raymond, who at times relies verbatim on reports by Charles Frost, a skilled promoter and self-promoter, reports that this party of prospectors was under the leadership of none other than Frost himself! But in fact Dan Brown was regarded to be the leading prospector of early Philipsburg, since an assembly of miners gathered to organize the district elected him President. He was buried in Philipsburg and the GCHS has placed a marker on his grave.
It is likely that the Brown-Frost party came into the Bitterroot Valley from Idaho, and heard of the shortcut through the mountains taken years before by John Owen, William Graham, and Fred Burr. As they checked out prospects near their route, they likely spotted Hector Horton's stakes at the Cordova lode. The seasoned prospectors in this group would have immediately recognized the potential signaled by the showings at the Cordova and started to search the hills for silver outcrops. Their arrival in the district was serendipitous, with several of the party making good money staking and selling claims, including some that would become major producing mines, like the Speckled Trout and Algonquin. Based on their discoveries, several of this party should be considered to be first-rate prospectors, in Horton's league.
In 1866, mining claims were staked in lots 200 feet along the vein and 100 feet wide. The discoverer could claim the Discovery lot, and one other along strike. The rest of the lots, up to 5 on each side of the Discovery, were put in the names of relatives, friends or business partners. A claim could therefore have up to 11 lots and be 2200 feet long. There was no requirement that any person actually be present on the ground except the discoverer.
Here is a roll call of the discoveries of 1866 that eventually proved to be good silver mines.
Hector Horton: returned to the district shortly after the Brown-Frost party arrived and located the Cliff and Horton veins, both eventually developed to 1000 feet of depth and multi-million ounce producers.
Dan Brown: the Comanche lode, one of the richest outcrops on Hope Hill and a producer through the 1970s, also the Algonquin vein, a large silver and manganese producer developed to 1000 feet of depth,
Charlie Frost: the Speckled Trout, eventually a good mine, and several others, among which was the Poorman's Joy, which proved the downfall of James Stuart.
James Estill and his brother: Salmon lode, part of the Scratch All group that later developed into a major silver producer. Estill had been mining in the Garnet District (Flint Chips). It's possible he learned of the district when the claims were recorded at Silver Bow, or simply by "the grapevine". James Estill was another first-rate, successful and ultimately prosperous prospector, with a piece of the discovery of many Philipsburg claims, including the famed Granite Mountain nearly a decade later.
The summary of USGS geologist William Harvey Emmons states that the district was first brought into prominence by Frost when he displayed high grade specimens in Helena. But that is not what brought the rush of prospectors and miners to "Flint" in early 1867. Rather, it was the announcement by the St. Louis and Montana Mining Company that they were going to build a mill. Hector Horton initiated the interest of that Company in Flint, not Frost.
By mid-summer mining claims were being staked with reference to three cabins: Horton's near the Cordova (within what would become the townsite of Philipsburg), the Brown/Franklin cabin or cabins (very probably located along Camp Creek next to the future site of the Northwest Company mill, since later reports say this cabin was near "Cole Saunders' smelter", which became the NW Co's millsite). and Mathias' cabin (apparently located in what would become the yard of the Algonquin mine).
In his report to the bondholders of the St. Louis and Montana Mining Company in 1873, Felix McArdle (d. 2/23/1874) reports that the first 2000 feet of lode claims bought by the Company were almost worthless with the discoverer in some cases proving unable to even show the location on the ground. These claims were: Gold and Curry, Ledger, W.B. Dance, Legal Cap, Wabus, Lord Byron, and Decope Chickoman. Horton was the discoverer, but the lots sold were not his discovery lots, but other lots along the vein that belonged to Anderson, Dance, and Stuart. According to a document in MHS, they attempted to sell this claim footage to the St. Louis and Montana Mining Co. for $100,000 in stock. The sale recorded in the courthouse is for $500 cash, but perhaps stock was a second, unmentioned "valuable consideration." In any case, it would be understandable if Horton didn't care to show the discoveries, because he had been cut out of the sale.
One major claim is absent from this discussion - the Hope Lode. Contrary to USGS PP78, this claim was not located by Horton, and was not located in 1864. It was located in July of 1867 by Reece Anderson. However, a later report in the Anaconda Standard stated that the honor of the discovery of the Hope mine actually belonged to Rory McRae of Stone Station.
When the St. Louis company, which first purchased the Comanche claim on Hope hill began work on it, McRae was employed as a carpenter, his duties being to cut timbers for the mill, which was then in the course of erection. The Comanche was a rich claim, but the ore shoot was small and the mine soon "pinched out." McRae's work brought him frequently to the top of the Hope hill. Returning one evening, he picked up a piece of float rock which bore the unmistakable traces of mineral. He broke the quartz with his axe and on his his way home showed the rock to Anhauser, Anderson, and Stewart who were then employed at the old Hope office. Anhauser was the son of a St. Louis brewer and could not distinguish a piece of rich float from a keg of his father's foamy product, and Anderson and Stewart were equally as ignorant of mining. They "jollied" McRae into the belief that the rock was not worth assaying, but ascertained the spot where McRae found it. That evening they showed the rock to Dr. Merrill, who was then assayer at the Hope mill. Dr. Merrill at once pronounced the rock rich in silver. Before daylight the next morning Anhauser, Anderson and Stewart found the ledge, located the Hope mine and soon afterward sold the property to the old Hope company for a good round sum.
The Hope was one of several lodes sold by the Stuarts, Dance, et al, to the St. Louis and Montana in 1867 for $25,000. It is likely that part of the sale price was reimbursement for the purchase of the Comanche lode and other claims, and part for the Hope itself, which proved to be an excellent mine.