Published by The Flatirons Mineral Club
Volume 47, No. 6 June 2005
Flatirons
Facets is published monthly by The Flatirons Mineral
Club. The deadline for submission of articles to
Flatirons Facets is the 20th of each month.
Permission is granted for reprint if credit is given
to the publication and author unless specifically
restricted.
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Flatirons Facets
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P. O. Box 3331
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Boulder, CO 80307-3331
The Flatirons Mineral Club is
a non-profit organization, established March 9,
1957, and dedicated to developing and maintaining
interest in all aspects of earth science and
associated hobbies. The club meets the second
Thursday of each month at 7 p.m. We meet at
The Senior Center, 9th and Arapahoe Avenue,
Boulder, CO. Guests and visitors are welcome.
Membership dues are $15.00 per year (beginning
October of each calendar year). People interested in
membership can contact the club either by writing to
the above address or by attending one of the
meetings.
Deadline for the July Facets is
June 20.
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President's
Corner Dennis Gertenbach The big club event in June is the Silent Auction on Thursday night, June 9. Members are encouraged to bring specimens, lapidary works, supplies, books, maps, and other rockhounding items to sell at the auction. This is one of the club's major fundraisers of the year, with the club collecting 25% of the proceeds (or more, if you choose) to help with club expenses. Auction sheets are attached to this newsletter. Also, you'll find some great bargains, so come and purchase additional specimens or supplies. Also, there is a special table just for kids. Be sure to sign up for the upcoming Field Trips, including the RAMS claim in Crystal Peak area to collect amazonite, smoky quartz, and topaz on July 16 and the Florissant tour of CU paleontology dig on July 17. You can contact Gerry Naugle to sign up for these trips. More trips are in the planning stage, so watch for announcements in upcoming newsletters and at the monthly meetings. Happy rockhounding,
**************** Our annual silent auction takes the place of our June Meeting (Thursday, June 9), and is held at our usual location and time (West Boulder Senior Center, 9th & Arapahoe, 7:00 PM). See the announcement in the President's Corner above. We will not have a July meeting this year, but instead, we will have a weekend picnic and dig with the Mile Hi Rock and Mineral Society (RAMS) at their claims in the Crystal Peak area. See the next item for details. In place of our August club meeting, we will be having our annual club potluck picnic in North Boulder Park on Sat. August 20th at 4:00pm, members and immediate families. The club provides hamburgers, soft drinks & water. Last names A-M please bring a salad, last names N-Z please bring a dessert or watermelon. RSVP to Gerry Naugle by Aug. 18th. So after our silent auction on June 9, we won't be back at the Senior Center until the September meeting. **************** RAMS Picnic, July 16-17 There will be a joint picnic and digging field-trip weekend with the RAMS Club at the four RAMS crystal digging claims near Crystal Peak area of the Tarryall Mtns. on the weekend of July 16th and 17th. Potluck picnic and BB-Q (meat, chips and soft drinks provided by RAMS) at noon on July 16th at a BB-Q pit near one of the claims. FMC is going to provide and bring an iced new large container of potato salad and watermelon. Rendezvous spot is set for 10:00am on July 16th not too far from Lake George. Dry camping at the claims on that Sat. night. Side trip over to the Florissant Fossil beds on Sunday afternoon. For further information, map and details and to RSVP for this field trip, please contact Gerry Naugle before July 8th. Note: Good boots, picks, chisels, pry-bars, rock-hammers and eye protection (safety glasses or goggles), and first aid kit suggested/required while digging in the claims. Lots of good crystals have come out of there. **************** Jr. Geologists Begin Summer Outings Now that summer is here, the Jr. Geologists will be out in the field each month, studying the geology in our area. (With good weather, who want to be inside?) The next Jr. Geologists night will be on Thursday, June 16. The field trip will count towards the requirements for the Fossil badge. Please contact Dennis Gertenbach for details of the trip. The Jr. Geologist program is open to all club families. We meet monthly to learn more about rockhounding and the earth sciences. For more information contact Dennis. **************** Spring & Summer Hazards Now that the warm weather has returned and we are all again outdoors prowling for treasure, don't forget about the usual hazards such as ticks, mosquitoes and sunburn, and remember to take insect repellent and sunblock with you on your outings. **************** New Art Gallery Seeking Artists, Artisans
Alicia Griggs is pleased to announce the opening of the Elements Art Gallery at 2616 W. Colorado Avenue in Old Colorado City. The gallery represents art from Colorado Artisans. The Elements Art Gallery is open most days and always Thursday thru Sunday from 11 am - 6 pm. Always by appointment. Call 719-633-3899, or 719-685-3777 for more information. Types of artists wanted: Photographer, Oil Painter, Goldsmith, Ceramic Artist, Fiber Artist, Freeform Glass Artist, Metal, and Wood Artist. http://www.manitouartists.com, Now showing at The Business of Arts Center, Manitou Springs, CO. ****************
FMC Fall Show Committee
News Plans for the November mineral show are moving right along. At a meeting of the committee May 17, a number of matters relating to the show were discussed, including the fact that we would really like to reach out to children as much as we can. Jim Armitage, who is back with us for the summer after his winter sojourn in Arizona, is planning to send out letters to as many schools as possible toward the end of August to try to get greater participation. We appreciate the volunteers who gave of their time last year to make the children's wheel, grab bag sales and dig site a success. Speaking of the dig site, we are in urgent need for more rocks, ping-pong to baseball size, for this project. If you have material of this nature, please contact Charlotte Morrison. Our thanks to Kate Goss, who has volunteered to help with children's activities this year. Gerry Naugle talked about how important it was to have signs advertising our show all over the neighborhood. He said that lat year a large portion of the signs were removed or stolen, but we did get a lot of good publicity from those that were left. We hope we can get volunteers again to distribute signs this year. Gerry also stated that the Boulder Library is going to give us a large display area again this year to promote our show and has offered to let us run an article in the library newsletter later this summer. Charlotte Morrison is going to be in charge of the fluorescent room again, and hopes to have some cases to display materials that will give us a little better security than having specimens lying out on a table where they can be walked off with. We are still looking for help in the area of lining up people for various jobs, and especially need someone to be in charge of giving out the door prizes. If you would like to work on the committee, we would love to have you. Our next meeting is at Charlotte Morrison's house July 19th at 7:15. Please come if you can. **************** Prizes for the Flatirons Mineral Club November Show The grand prize door prizes for our November show have been chosen and are pictured on the club's web page. Show date is Nov. 18th to 20th at the Boulder Elks Lodge, and two dollars per person per day admission (gets) folks a chance to take one of these (pictured) home after the show. In the photo, from the left are: two large Trilobite halves from Morocco, a cluster of Pyrite-replaced Ammonites from the Volga River area of Russia, and a cut Amethyst Geode from Brazil. (Photo by Gerry Naugle) ****************
Earth Science Things to
do This Summer * Visit the USGS Map Store in Building 810, Denver Federal Center (Kipling Ave. north of Alameda), Core Research Center, entrance S-25. The Map Store sells USGS topographic, geologic, and all other maps & publications, as well as other books/maps/videos/CDs about nature, wildlife, geology, etc. (and yes, even Audubon Society singing birds!). Open 8-4 weekdays, located at the SW corner of Building 810. The Store is now run by the Rocky Mountain Nature Association; telephone number is 303-202-4700. To browse some of our most popular maps ahead of time, see (among other urls) http://rockyweb.cr.usgs.gov/outreach/mapcatalog/ * A good assortment of similar items and displays (emphasizing, but not limited to, dinosaurs) is available at the Dinosaur Ridge Visitors Center, 16831 W. Alameda Parkway, Morrison CO 80465, telephone 303-697-3466. Open 9-5 Mon-Sat., 12-5 Sun. While there, take the walking or driving tour of Dinosaur Ridge (Alameda Parkway, as it crosses the Dakota Hogback), and/or walk the Dakota Ridge Trail, along the crest of the hogback; check out the Technicolor Stegosaurs painted by various local art groups under the trees outside the Visitors Center; and come to one or more of the "Dinosaur Discovery Day" public tour days, coming up on June 4, July 2, Aug. 6, Sep. 3, and Oct. 1. P.S., one item available in the Dino Ridge gift shop is a little boxed set of the Colorado State Rock, Mineral, and Gemstone (marble, rhodochrosite, and aquamarine), sold as a fund-raiser by Girl Scout Troop 3010, the group that successfully petitioned the State Legislature to declare marble the State Rock of Colorado in 2004. (The set includes an actual faceted aquamarine gemstone.) * For a neat place to see and explore fossil displays as well as live reptiles, amphibians, and ecology, visit the Morrison Natural History Museum, 501 Colorado Highway 8 (1/3 mile south of Morrison, on the road to The Fort and US-285), open 10-4 Tues.-Sat. (10-5 after Memorial Day), 12-4 or 12-5 Sun. Adult admission is $4, progressively smaller kids are less. See http://town.morrison.co.us/mnhm/hours.php or call 303-697-1873. Memorial Day weekend is "Jurassic Adventure Weekend" with Dr. Robert Bakker and others at the MNHM; see http://www.dinoridge.org/news/index.html for details. * Visit and walk the "Walk Through Time" interpretive geologic rock trail, located next to the Green Belt behind Broomfield Heights Middle School, Broomfield.Open any time; see http://student.bvsd.k12.co.us/~bmeier/walk/dev/index.html * Two more outdoor geologic walking tours exist in Golden: the "Triceratops Trail" at "Parfet Prehistoric Preserve", a short interpretive trail to see dinosaur tracks plus those of other vertebrates and invertebrates, plant fossils, etc. Located just off the bike path along Highway 6 in Golden (access the bike path from the crosswalk at 19th St. and Highway 6), at the northwestern-most edge of the Fossil Trace golf course. A brochure about the site is available at the Dinosaur Ridge Visitors Center. and... On the Colorado School of Mines campus, a couple of blocks from the new CSM Geology Museum (also very much worth seeing; free admission, located at 13th and Maple Streets, open 9-4 Mon-Sat., closed Sundays during the summer) is a short geologic walking tour of the rock exposures at the edge of campus, including a "Rock Garden" (no garden really, just rocks) featuring rock samples from all the geologic formations exposed nearby. A brochure about the tour is available at the CSM Museum, or see the CSM Geology Department's website. To see the "Rock Garden", walk or drive one long block south (uphill) from the Museum on Maple Street; turn right (west) on Campus Drive; where the drive curves to the left, turn right into the large Freshman Parking Lot; the "Rock Garden" is at the far, north edge of the parking area. * Sign up for one of the free Map & Compass and GPS (Global Positioning System) classes held the 2nd Friday of each month, 9-11 a.m. and 12-4 p.m., at Building 810 on the Federal Center. Dates are June 10, July 8, Aug. 12, Sep. 9, Oct. 14, Nov. 11. For info call 303-202-4640. * One last thought, if you're at the USGS/RMNA Map Store, take a look (ask for a copy; they are free) of newly published USGS Circular 1274, "Celebrating 125 Years of the U.S. Geological Survey". The 56-page illustrated booklet describes the historical background of, and current research done by, the USGS, including capsule biographies of a number of USGS scientists and what they do. A selection of other free USGS brochures is also available there. **************** Upcoming Events, Nearby & Elsewhere Saturday June 11, USGS geologist Dr. Pete Modreski will lead a field trip for the Colorado Scientific Society: South Platte Country field trip, the White Cloud Pegmatite + the 1996 Buffalo Creek fire and flood. "A field trip to visit (1) the White Cloud Pegmatite, part of the South Platte pegmatite district within the Pikes Peak batholith, and (2) to see erosion, sedimentation, and ecological recovery in the aftermath of the June 1996 Buffalo Creek forest fire and flash flood. The trip will involve a 2-3 mile (round trip) hike beginning at the Colorado Trail footbridge just south of the confluence of the North and South Forks of the South Platte River. The hike will take us partly on the Colorado Trail, off-trail down a steep 400' hillside, and downstream along the wide gravel bed of Spring Creek". The trip is sponsored by the CSS but anyone may attend, space available; there is an $8 registration fee. The trip will leave at 8 a.m. from the Cold Spring Park and Ride, Lakewood; contact Pete at 303-202-4766 or pmodreski@usgs.gov for details. June 11 - 12, 2005, Powell, WY, Wyoming State Mineral and Gem Show - "STONES and BONES", Park County Fairgrounds, 655 5th St. Hosted by Shoshone Rock Club. Show information: www.geocities.com/jacmac43hng-show05.htm .For further information contact: Mrs. Jane R Neal 1207 Rd 9 Powell WY 82435, 307-754-3285 or Mrs. Mary Ann Northrup, 736 Lane 13 Powell WY 82435, 307-754-4472. June 17 - 19, 2005, Colorado Springs, CO, The Colorado Springs Mineralogical Society will be hosting the Rocky Mountain Federation of Mineralogical Societies Show at its 41st annual Pikes Peak Gem & Mineral Show. The theme will be "Pikes Peak, A Rockhounds Paradise", featuring Colorado Gems, Minerals and Fossils. Five days of field trips will follow the show. CSMS will this year also be hosting The Rocky Mountain Micromineral Symposium. The symposium is co-sponsored by The Denver Museum of Nature and Science and The Friends of Mineralogy. For more information, call us at (719) 632-9686, e-mail us at csmsshow@cs.com or visit our website at www.csms.us. Location: Phil Long Expo Center, 1515 Auto Mall Loop, Colorado Springs, CO. Aug. 11-14: Contin-Tail Rock Swap and Mineral Show, Rodeo Grounds, Buena Vista, CO Aug. 19-21: Lake George Gem & Mineral Show, for more information contact Richard Parsons at 303-838-8859 or tazaminerals@att.net. Sep. 10-11: Mineral Symposium sponsored by the Colorado Chapter, Friends of Mineralogy, "Agate and Cryptocrystalline Quartz", to be held at the Green Center, Colorado School of Mines campus. Registration fee is $40, Saturday evening banquet $25, plus optional field trips. Sep. 16-18: Denver Gem and Mineral Show at the Denver Merchandise Mart, 58th Ave. and I-25. Check Flatiron Mineral Club’s own web site for additional events, and further details:http://bcn.boulder.co.us/community/fmc/fmctk.htm ****************
Colorado Mine Tours And
Mineral Museums Planning your Summer vacations? Why not visit one of the mines or mine-related museums here in Colorado? This listing courtesy of the Colorado Division of Mines and Geology website.
Argo Gold Mine and Mill
(tour)
Bachelor Syracuse Mine
(tour)
Clear Creek Mining and
Milling Museum
Colorado School of Mines
Geology Museum
Country Boy Mine (tour)
Creede Underground
Mining Museum
Cripple Creek District
Museum
Denver Museum of Nature
and Science
Edgar Mine (tour)
Gilpin County Historical
Society Museum
Hard Tack Mine (tour)
Hidee Gold Mine (tour,
appointment only)
Lafayette Miners Museum
Lost Mine Tour
Lowell Thomas Museum
Lebanon Mine (tour) and
Georgetown Loop Railroad
Matchless Mine (tour)
Mayflower Mill (tour)
Mollie Kathleen Gold
Mine (tour)
National Mining Hall of
Fame & Museum
Nederland Historical
Society and Museum
Ouray County Historical
Society and Museum
Old Hundred Gold Mine
(tour)
Phoenix Mine (tour)
Smuggler Mine and
Compromise Mine
Walsenburg Mining Museum
Washington Mine and
Lomax Placer (tour)
Lomax Placer (tour)
Western Museum of Mining
and Industry ****************
The Nature of Rocks and
Minerals It is necessary to learn about rocks so that we can have a better insight into an area's geologic past and to help us determine what type of minerals we could expect to find. As a short review, let us remember that "A mineral is an inorganic substance whose composition can be expressed by a definite chemical formula, and which has a definite internal structure which manifests itself in a certain crystal shape." Rocks are composed of one or more minerals. Rocks are classified and named by their mineral constituents and grain size. Some monomineralic rocks are sandstone, quartzite, salt, gypsum, limestone, dolomite, marble, and phyllite. There are three main groupings of rocks: igneous, sedimentary, and metamorphic. The origin of these rocks are reflected in their structures, textures, and mineral compositions. Igneous Rocks Igneous rocks are formed by solidification of mobile material termed magma, and are composed of interlocking mineral grains. Igneous rocks that cool beneath the earth's surface are called intrusive or plutonic rocks, while those that form on the surface are called extrusive rocks. Rocks that cool within the earth do so slowly and are characterized by having medium to large interlocking mineral grains, such as pegmatitic textured rocks. Rocks that form on the earth's surface cool rapidly and have small to microscopic interlocking mineral grains. Rocks which chill very quickly can form glass. The color in glass - obsidian reflects its composition. Sometimes a lava froth may cool to form pumice. Gasses trapped in its matrix cause the rock to float. Where gasses escape, holes are left behind such as in scoria. An example of an igneous rock composed of two minerals is; granite -quartz and feldspar. Sedimentary Rocks Sedimentary rocks are formed from precipitation from solution, or by deposition through wind, glacier, and running water action. These types of rocks are characterized by having round grains held together by some cementing material, and show layering. Any pre-existing rock can be broken down by the agents of erosion and be deposited as grains. Sedimentary rocks can be further sub-divided into being formed by chemical precipitation or mechanically deposited. Rocks deposited through precipitation are limestone, dolomite, and chert, while those laid down through mechanical deposition are sandstone, glacial till, conglomerates, and breccias. Sedimentary rocks can contain more than one mineral. The degree of the mineral grain's rounding depends upon the distance it raveled as well as its hardness. An example of both extremes is fine grained sandstone. Metamorphic Rocks Metamorphic rocks form in solid state from pre-existing rocks in response to pronounced changes of temperature, pressure, chemical solutions, and combinations of the above. These types of rocks are characterized by aligned mineral grains as seen in some marbles and schist, layering as seen in slate, schist, and phyllites, and banding as in gneiss. All mineral grains are aligned in response to regional pressures exerted on the rocks. Nonfoliated metamorphic rocks include marble and quartzite, foliated ones are gneiss and schist. Rocks are constantly changing from one type to another. Yet we can still tell the general geologic history of an area by looking at the rocks that make up the region. **************** Return to Facets Index
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