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| One of the beautiful national parks I visited was Crater Lake n.p. in Oregon. Formed from the shattered remains of an eruption some 7700 yrs ago, the lake is some 592m deep and 9.6km across at it's widest point. | The pinnacles, beside Crater Lake, are a colourful collection of 30m tall spires that are being eroded from the canyon walls. The spires are 'fossil fumeroles', each marking a spot where volcanic gas rose up through hot ash deposits, cementing the ash into solid rock. |
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| The 'John Day Fossil Beds', (Oregon) Painted Hills Unit. The hills are the result of the erosion & weathering of volcanic ash under a variety of climatic regimes. The area has yielded many excellent fossils. | The 'John Day Fossil Beds', Sheep rock unit has the visitor information centre with fossil exhibits. This fossil skull has been distorted by pressures underground, making it difficult to identify. |
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| A staff member at The 'John Day Fossil Beds' undertaking work on fossils recovered locally. | A fossilised skull at the 'John Day Fossil Beds', Sheep rock unit. |
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| Butte, Montana, has been a major copper mining area, with a large open cut pit replacing underground mining in 1955. The mineral museum has a nice display of minerals and gemstones. | Butte museum, Butte, Montana. Sulphur specimen. The museum is located on the Montana Tech Campus. It has over 1300 minerals on exhibit, including a 27.5 oz gold nugget. |
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| Butte museum, Butte, Montana. Flourite specimen. | A geyser in Yellowstone n.p. The last major volcanic eruptions occurred around 640,000 yrs ago. The central caldera, some 75km across, is still underlaid by magma which still powers the parks geysers, hot springs and mudpots. |
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| Old Faithful Geyser, erupts at intervals which have varied from 40 to 126 minutes. The time of the next eruptions can generally be predicted to within about 10 minutes at present. | The Badlands np in South Dakota show the effects of sedimentation and erosion over some 75 million years. It is a source of many fossils. |
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| Mt Rushmore, South Dakota. This is a rather impressive example of stone 'carving' compared to what most lapidaries do! Constructed between 1927 & 1941, using dynamite and jackhammers plus 400 workers; each face is 18.3m high. The presidents (L to R) are George Washington, Thomas Jefferson,Theodore Roosevelt , Abraham Lincoln | There are plenty of rock shops in the mining states such as Montana, South Dakota, Colorado & Arizona. Lapidary shops are less common. This shop is in Custer, South Dakota, near Mt Rushmore. |
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| Some of the petrified wood on display. Note the 'wood' from arizona (red, white & yellow). I saw magnificent polished sections of tree trunks (1m in diameter) of this material at Bryce canyon in Utah | There are many nice agate specimens in the rock shops in the USA! |
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| The shop had a wide range of rocks, fossils & minerals on display. | You can purchase more than just 'rocks' at this shop. |
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| A place well worth visiting is the 'Mammoth site' at Hot Springs in South Dakota, just south of Mt Rushmore. A large number of male mammoth fossils are preserved in situ. | The many mammoths that died in what was a sinkhole, are slowly being excavated by paid staff and volunteers. The site dates to approx. 25,000 years ago. |
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| This specimen is cvered by gem quality beryl crystals, up to 10mm wide. The full specimen is shown to the right (the photo does not do it justice). One of many high quality specimens at the Denver Museum of Natural History, Denver, Colorado | This specimen was dug up in the last few years by a fossicker. It measures approx. 1m high! |
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| The Denver Museum of Natural History is well worth a visit by lapidaries and mineral collectors. It has a fantastic collection of minerals & gems. Above are some crystals of aquamarine and tourmaline. | A display of agates at the denver musuem of natural history. |
Below: some of the
lovely rhodochrosite specimens at the museum. Right: the 'rhodo pocket' from the famous 'Sweet Home Mine', covered with gemmy rhodochrosite crystals. Approx. 3m long by 2m wide. |
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| The famous 'Alma King' rhodochrosite specimen. The main crystal is approx. 6" across. | |
 The 'Alma King' specimen measures some 1m high and is covered with fine quartz, calcite and flourite crystals as well as the magnificent 'Alma King crystal'. Well worth a visit. |
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| A display of gold leaf specimens at Denver Museum, Colarado. Part of a larger collection of gold specimens. | A closer view of the 'rhodo' pocket from the Alma King mine. |
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| The Colorado School of Mines Geology Museum, in Golden, Colorado, has been in it's impressive new two storey building since 2003. The current director, Bruce Geller & his staff are very welcoming and informative. Well worth visiting! | A lovely specimen of Elbaite on Albite (200mm wide). One of many high quality specimens at the Colorado School of Mines Geology Museum |
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| Flourite on Sphalerite, Colorado School of Mines Geology Museum | Shorl on Albite v. Cleavelandite |
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| A view of a small part of the interior of the Colorado School of Mines Geology Museum | Apophyllite with Stilbite from India, Colorado School of Mines Geology Museum |
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| One of many displays of gems at the Colorado School of Mines Geology Museum. The museum has very informative labelling of it's displays. | The fossil displays at the museum are set up in a clear, informative way. Grouping the fossils into their relative geological eras provides a good sense of the progression of fossils through those eras. |
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| Part of another display of high quality gems at the Colorado School of Mines Geology Museum, the peridot in the centre is a flawless 130.47ct gem. | A Rhodochrosite specimen to die for! |
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| The 'Colorado Fire Necklace', featuring a magnificent collection of faceted Rhodochrosites, is on of the attractions at the Colorado School of Mines Geology Museum. | |
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| A lovely Aragonite specimen at the Colorado School of Mines Geology Museum. | Monument Valley, Arizona. |
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| Bryce Canyon, a classical example of differential erosion, is one of the most beautiful national parks in the U.S.A. and a 'must see' for any visitors. Water erodes the rock both mechanically (when fast moving water, carrying sediments abrade the rock) and chemically (as slow moving water enters the rocks and dissolves the 'natural cements' holding the grains of rock together. | |