What is the distinctive structure all these have in common? They often are composed of basaltic lava flows that cooled to form “columnar basalt.” Columnar basalt exhibits massive, vertically standing columns. Although usually hexagonal (six-sided), such columns are polygonal (multi-sided) and may have anywhere from three to 12 sides. They are often so uniform in size and shape that they seem to have been artificially constructed, like giant columns of poured concrete. But these columns most definitely were not crafted by the hands of humans!
Rather, they are natural formations resulting from the cooling of thick outpourings of lava. Under certain conditions, lava contracts as it cools.
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ROOSEVELT DAM AGATE: A Gem Loaded with History
The Roosevelt Dam agate is a very limited-occurrence lapidary material, uncovered during the excavation of the Theodore Roosevelt Dam in Arizona, hence the obvious name of Roosevelt Dam agate.
GEORGIUS AGRICOLA'S: DE RE METALLICA
465 Years Old and Still Relevant
Trisparkle 12 Design Marks New Approach
I want to thank Jim Perkins for his many years of providing outstanding faceting designs for the Rock & Gem readership.
Scientists Looking at a Possibly Undetected Volcano in Alaska
Is there a previously undiscovered volcano within Alaska’s Aleutian chain of islands? A team of scientists recently presented their findings surrounding this possibility during a meeting of the American Geophysical Union (AGU).
COMMON, BUT NOT CONVENTIONAL
Discovering the Splendor of SLAG
A pile of slag remaining from copper smelting operations of 1930s Cottonwood, Arizona is one area of focus for Minerals Research, Inc. (MRI), the company pursuing a 15-20 year process to remove the pile using innovative recovery technology.
HUNTING FOR THUNDEREGGS
Uncovering A “Ghost” Volcano’s Treasures
GALENA’S GIFT OF A STUNNING SECONDARY MINERAL
Anxiously Awaiting a New Museum Opening
With the year 2021 upon us, Arizona collectors are certainly excited about the pending May opening of the University of Arizona Alfie Norville Gem & Mineral Museum in downtown Tucson. Of course, the excitement extends beyond the border of Arizona and to far reaching locales around the globe.
Captivated By Copper
Soldiers’ Discovery Leads to a Century of Mining at Pearl Handle Open Pit
A SPONTANEOUS CRUISE ALONG SCOTLAND’S WILD WEST COAST PROVED TO BE A VOYAGE OF SURPRISES FOR PHIL JOHNSON
A Wee Dram
There’s more to love about Scotland’s favorite libation once you discover the magic
Through the Wire
Taking Scotland in Stride
A walk through the Highlands and Borders is the best way to touch this country’s history and nature
Scotland Makes Periods Less Painful
The country is the first in the world to offer free, universal access to sanitary products
A REACH TOO FAR
This is not the story I thought I’d be writing when I began my motorcycling adventure on Namibia’s gravel roads.
With cruises that visit South Africa, Botswana, Namibia, and Zimbabwe, CroisiEurope shows off the best that land and water have to offer.
Can An Unlove Child Learn to Love?
Thirty years ago, the world discovered tens of thousands of children warehoused in Romanian orphanages, deprived of human contact and affection. They’re adults now.
Bass of Tomorrow
We can think of a few string manufacturers who claim to make the best-sounding products in the world. Dr Jonathan Kemp doesn’t just make that claim—he can prove it, too. Hywel Davies is blinded with science...
A JOURNEY FROM THE HEART OF NAMIBIA TO THE SKELETON COAST IN LAND ROVER’S STUNNING NEW OFF-ROAD CHAMPION