Arizona Collecting Sites
Arizona Collecting Sites
Apache Powder Plant Site near Benson, Arizona
Selenite Roses, Banded Rhyolite
Source: Gem Trails of Arizona ISBN 935182-42-X ©1989
Selenite roses and stars are to be found in the flat-topped hills southwest of the Apache Powder Plant. Try digging in soft, reddish-brown areas of the soil. You'll need to dig and handle the selenite carefully to recover intact specimens. This material is not as fragile after it's initial exposure to air.
A colorful, banded rhyolite is also to be found at this collecting site.
This site has excellent access. To get there, go south from Benson on Highway 80 for 5 miles and then turn onto Apache Powder Plant Road. Follow Apache Powder Plant Road for 3.5 miles, passing the Apache Powder Plant on the west side of the road. At 3.5 miles down Apache Powder Plant Road, look for ruts to the west leading towards the hills about a mile away. Follow these ruts to the hills.
Diamond Point and vicinity near Payson, Arizona
Clear Quartz Crystals, Geodes, Blue and White Agate
11-26-01 Update: Diamond Point has been closed to digging by the Forest Service. Digging of any kind or breaking rocks is prohibited. Punishable by a $500 fine and/or six months in jail. They have closed off over 4000 acres.
Source: Gem Trails of Arizona ISBN 935182-42-X ©1989
Clear quartz crystals, many of them doubly terminated and resembling New York Herkimer diamonds, are to be found at Diamond Point. Easiest pickings are to be had after heavy rains have exposed previously hidden crystals. Pockets of crystals which can be productively worked by digging are also to be found toward a fence overlooking a cliff. Look for signs of excavations by previously visiting rockhounds to help locate this area.
To reach Diamond Point go northeast from Payson on Highway 260 (Star Valley Road) for about 14 miles. Turn west on Forest Road 64 before reaching the Kohls Ranch. Follow Forest Road 64 west for 4 miles; then turn south on Forest Road 65 and follow it for about 3.7 miles before pulling off the road and parking.
Another site near Diamond Point is a good place for collecting geodes, which are found just lying about on the surface. The size of the specimens vary from .25" to 10" in diameter. A bubbly tan is the most common exterior appearance. Geodes with darker brown to black exteriors are also found here. Blue and white agate can also be collected at this site.
To get to this geode site go west 8 miles on Forest Road 64 from the intersection of Forest Roads 64 and 65 (3.7 miles from Diamond Point). When you've traveled 8 miles, stop and check out the ravines, hillsides and eroded areas on both sides of Forest Road 64. If you reach the bridge over a creek on Forest Road 64 you've gone a mile too far west of the main deposit.
Hull Mine near Yuma, Arizona
Calcite, Fluorite, Galena, Quartz, Wulfenite and possibly Vanadinite
Source: Rocks-and-Fossils Mailing List 5/23/95 & 5/25/95
Richard Busch
busch.dsc@xerox.com
As part of my three-day swing through southern California and southwestern Arizona a couple of weekends ago, I visited the Hull Mine, located in the Castle Dome district NE of Yuma, Arizona. Although fluorite was not the principal mineral mined there, I found some nice, blue, fluorite cubes (about one-half inch on each edge) on a crystallized galena and country rock matrix, galena crystals, calcite, quartz, and one specimen of wulfenite. Vanadinite is reported, but I didn't find any.
The Hull Mine is an abandoned, underground mine in a field of mineshafts which comprise one of the primary mining areas in the Castle Dome district. Although I am normally wary of entering abandoned mines, I regard this one as relatively safe as long as one carries an adequate source of light. One of the entrances is an adit which slopes downward at an angle of approximately 15 degrees and tunnels into the base of a hill. Shafts on the other side of the hill intersect the underground tunnels. The result of this is a very nice breeze which flows through the mine and provides fresh air while underground.
The Hull Mine is not timbered, which is good. This means that the miners felt the surrounding rock was strong enough to support the roofs of the tunnels. (I don't go into old, timbered mines. The timbers were put there to support the roofs. After many years the timbers rot and weaken, thereby increasing the danger of collapse. No mineral specimen is worth my life.)
A companion and I entered through the aforementioned adit. The tunnel is high and wide enough for three people to stand in side-by-side. The floor of the tunnel is dry and relatively flat. The only potential danger is from wires hanging from the roof of the tunnel (part of the old electrical system). Keep your eyes open, carry a good source of light, and watch where you're going.
We walked down to the 200-foot level, at which point we arrived at a T intersection. We took the left branch of the T and continued on for a couple of hundred feet to a pile of broken rock on the tunnel floor. It was this pile of rock, thoughtfully left by some previous visitors, in which we found the fluorite, galena, and my first-ever, self-collected specimen of wulfenite.
This was my first visit to the Hull Mine and I hope to return to continue exploring and collecting. Perhaps someone else who has visited this mine and knows more about its geology and mineralogy can provide more information about it.
A short, dated description of the Hull Mine is contained in "Geology and Mineral Deposits of Southern Yuma County, Arizona (Arizona Bureau of Mines Bulletin 134; University of Arizona Bulletin Volume IV Number 2);" by Eldred Wilson (1933).
The Hull Mine is shown just to the right of center on the 7.5 minute series Castle Dome Peak Quadrangle topo sheet. The adit I described in my previous message is located about 0.2 miles ESE of the Hull shaft and is marked with the appropriate symbol and the word "Adit" on the map. My GPS gives the location of the adit as N33x 03' 33" W114x 10' 31" (where the "x" means degrees since my keyboard doesn't have that symbol).
For those without ready access to the topo sheet (or a GPS), here are the driving directions (4-wheel drive is recommended but possibly not essential; the road is heavily washboarded in places):
Drive to milepost 55 on Arizona highway 95 (the road which connects Quartzsite and Yuma). Milepost 55 is about 30 miles north from the intersection of I-8 and Hwy 95 in Yuma; and about 45 miles south from the intersection of I-10 and Hwy 95 in Quartzsite.
Milepost 55 is about 100 feet north of the turnoff onto Castle Dome Mine Road, which heads roughly northeast. Set your trip odometer to 0 at the turnoff and refer to the mileages below (your odometer may vary slightly from mine).
Mile 0: Leave highway 95 heading roughly northeast on Castle Dome Mine Road which, at this point, is a 2-lane paved road.
Mile 1.8: The paved road turns right into a facility which features a red and white checkered water tower and some hangar- like buildings. Unpaved roads lead to the left and straight ahead. Do not follow the paved road. Continue straight on Castle Dome Mine Road which is now unpaved.
Mile 4.9: Drive past a large "Kofa National Wildlife Refuge" sign to the right of the road. (Trivia question: What does "Kofa" stand for? Answer below.) Continue straight.
Mile 5.0: Drive past (or stop at) a National Wildlife Refuge System information area to the right of the road. Continue straight.
Mile 8.2: The road forks. The intersection is marked by a wooden stake with the number "75" on it. Just past the stake is a larger sign reading "McPherson Pass 7 mi (with a forward pointing arrow)" and "Big Eye Wash 11 mi (with an arrow pointing to the right)." Follow the road in the direction of McPherson Pass.
Mile 8.3: The road forks again. The road which continues straight is blocked by a post embedded in the center of the road and a sign which reads "No Vehicles." Another sign, between the two forks, reads "Designated Road" and has an arrow which points to the left. Take the left fork.
Mile 8.7: A faint road forks to the right. It is posted with a "No Vehicles" sign and a "No Trespassing" sign. Continue straight.
Mile 8.8: Large signs posted on both sides of the road read "Castle Dome & Flora Temple Mines closed. No entry permitted. Private property. No trespassing. Dangerous mines. Keep out." You will notice a number of mine entrances, dumps, headframes, and "Posted" signs in this area. Don't stop. Continue driving on the dirt road.
Mile 9.7: The road forks. A "Designated Road" sign points to the right fork. Take the left fork, which leads through a broken yellow gate. You will notice several mineshafts in the immediate area.
Mile 9.9: Follow the road to the right. You should now be driving clockwise around a low (100-foot high) hill beneath which is located the tunnels of the Hull Mine.
Mile 10.1: You should now be to the west of the hill. The hillside is littered with old equipment, carts, pipes, small water and fuel tanks, prospects and shafts. Continue your circle around the hill, bearing right.
Mile 10.3: You should now be at the base of the hill, on its northeast side, at the adit to the Hull Mine. Enter carefully, take a lantern with you, and have fun.
bkeller@rockhounds.com 8/5/95
