This article was originally published by The-Vug.com in January, 2016
The-Vug.com brings you this article about Three days at the North Home Mine in Montana with Chris Tucker
Three days at the North Home Mine
Vanadanite, Wulfenite, Calcite, Descloizite, & More!
By: Chris Tucker
Sorry no images available, they were linked from a site that no longer exists.
Here the pillar has been removed. Note the numerous vugs lined with white calcite.
After removing the pillar and scaling the back and placing a stull for good measure, I examined the area for specimens. The rock in the pillar was laced with small calcite vugs, minor vanadinite, a few inner grown wulfenites, and patches of chlorargyrite. Along the left rib below where the pillar had been I noted a number of places where descloizite microcrystals were coating fracture surfaces. While the descloizite was not in big crystals, it was a colorful dark reddish purple and had lots of sparkle so I set about collecting a number of specimens. Farther down the left rib there is an area where vanadinite lines fractures. The vanadinite in this area of the mine generally occurs as both barrel shaped brown crystals and stout prisms that are white in color. After working the area for a few hours and only retrieving a few pieces, I called it quits for the day.
An image of the descloizite specimens that where retrieved from the area beneath the pillar. The heat cooked me awake early on Monday and I quickly made my way back into the No. 2 shaft. In the back of the stopped out workings above the 100 level is a large calcite lined cavity. I have known of this particular cavity for years but never made an effort to investigate it.
I placed a ladder below the cavity and climbed up to investigate it. The cavity is lined with snow white calcite with scattered crystals of vanadinite poking through the calcite; many of the vanadinites are coated by a parasitic growth of descloizite. Below and to the left of the cavity is an area of fair sized breccia fragments cemented by calcite; a number of small vugs are present in this area and one was lined with colorless calcite and lustrous descloizite on and after vanadinite. I found these to be fairly attractive and set about collecting a number of pieces.
After breaking for lunch and hoisting several loads of specimens out of the dark depths, I returned to collecting. Where the right rib meets the back at the 100 level is the January Pocket. Thus far, this pocket is the only significant source of wulfenite in the mine. I spent the next several hours working the remains of the pocket but was only able to obtain a few minor specimens. Although I worked the pocket area several feet back into the wall rock, no large cavities were found. There is still a persistent mineralized zone in the January Pocket area but the prospect of future specimens appears bleak and I probably won’t work the area again until I haul my compressor to the mine to do some drilling.
Here is a picture of the few remaining good wulfenites from the January Pocket. The largest wulfenite is about 0.7cm across. Like angles crying, a steady rain woke me Tuesday morning. Rain in August is not a common occurrence in the area; I took advantage of the cool weather to do some hiking and repair work to the access road. Mid afternoon I again entered the mine to continue my quest for some great prize.
I made my way down the main shaft to the 200 level. Along the back of the 200 is a string of pockets that are concentrated along the hanging wall side of the orebody. One of these pockets is the Little Muddy; this is the only pocket that has been found with any pocket mud; the mud has long since dried to a silky silvery grey powder. Only one specimen had been previously retrieved from the Little Muddy. The Little Muddy originally consisted of a long narrow tube extending directly into the surrounding rock. The mud in the pocket is fairly significant; it indicates a recent fluid flow in the area and an extensive conduit towards the surface. The mud is visually devoid of obvious oxides even though several hundred feet of the oxidized ore body lies directly above it. The pocket also happens to contain the most abundant concentration of plattnerite yet found in the mine. Vanadinite from the pocket ranges from greenish brown to brownish orange; the crystals are generally elongated prisms and lack the barrel shaped habit of the nearby Discovery Pocket. Though I hadn’t planned on collecting the area and I had figured that future specimens from the area would require drilling, I set up a ladder to investigate the area. A short distance from the pocket’s narrow opening I set about working the back with just a hammer and chisel. Within a few seconds I broke into a small calcite lined cavity. While probing the shallow depths of the cavity I noted some loose rock at the back. Quickly prying out the small loose pieces I was pleased to find a perfect 5cm vanadinite cluster hanging between the sides of the cavity.
General map of the 200 level of the North Home mine. Named pockets are shown in red.
Pockets shown in blue are either calcite lined or contain only minor amounts of vanadinite microcrystals.
The first six pieces recovered from the Little Muddy this trip. The silvery grey mud can be seen clinging several of the pieces. After removing the first few pieces I climbed down the ladder to gently place my new found treasures on a nearby ledge. Climbing the ladder again I removed some more of the surrounding rock to better expose the new opening to the pocket. While the rock around the pocket was solid, the rock forming the pocket walls was highly fractured and consisted largely of etched barite crystals.
Dried mud coated the bottom and sides of the cavity while the ceiling was clean. Laying loose in the cavity were clusters of vanadinite that had long ago fallen from the pockets ceiling and walls. Thankfully the soft mud had protected many of the specimens. Unfortunately, the natural “trimming” had produced a large number of thumbnail sized specimens and a few miniatures. (If anyone wants a wholesale flat of thumbnails from the Little Muddy, let me know and I’ll make you a screaming deal.) Many of the pieces also show some damage, which is to be expected in a collapsed pocket. I could attack them with air abrasives like other dealers and create “flawless” specimens, but that is not my cup of tea. Carefully picking through the loose material and trying not to drop anything would be the routine for the next few hours. Soon I had most of the contents of the cavity safely placed on the ledge some twelve feet below and I stood facing what would be the best piece recovered from the mine this trip. Measuring 15cm across and studded with 1cm vanadinite crystals along with thousands of lustrous black plattnerite microcrystals, the piece came out with just a minor amount of effort. The ever growing hole opened again beyond the piece and the now familiar jumble of crystals and rock fragments greeted me. Repeating the now familiar trip down the ladder with specimens and back to search for more, the hours flew by. Finally most of the easily collected pieces were safely below and only a few minor pieces remained firmly attached to the pocket walls. I’ll return at a later date to collect the remaining pieces and to follow any continuations of the pocket.
Wednesday morning I hoisted the last of the specimens and carefully packed them in the truck. I gathered my tools and locked the heavy steel doors that guard the underground workings. By noon I had everything in the truck and I was driving through the second of the gates on the access road, leaving the North Home and it’s mineralogical treasures behind me.
North Home Mine