Mit Magzter GOLD unbegrenztes Potenzial nutzen

Mit Magzter GOLD unbegrenztes Potenzial nutzen

Erhalten Sie unbegrenzten Zugriff auf über 9.000 Zeitschriften, Zeitungen und Premium-Artikel für nur

$149.99
 
$74.99/Jahr
The Perfect Holiday Gift Gift Now

ROOSEVELT DAM AGATE: A Gem Loaded with History

Rock&Gem Magazine

|

February 2021

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.

- HELEN SERRAS-HERMAN

ROOSEVELT DAM AGATE: A Gem Loaded with History

The Theodore Roosevelt Dam is located on the Salt River, northeast of Phoenix. The masonry dam was built between 1905 and 1911 and was renovated and expanded between 1989 and 1996. The dam is 357 feet high, with a hydroelectric generating capacity of 36,000kW. It was the first major project under the new federal law of 1902 - the Reclamation Act - which paved the way for irrigation projects to aid the arid western states’ settlement.

The dam sits at the confluence of Tonto Creek and the Salt River. The location of this narrow gorge was initially called “The Crossing” by early Arizona pioneers. It was the place on the Salt River where Native Americans, farmers, and ranchers would ford the river. The dam forms the artificial 21,500-acre Theodore Roosevelt Lake. The project’s primary purpose was to provide water storage and flood control through the Salt River Valley.

The dam is named after US President Theodore Roosevelt, who dedicated the dam on March 18, 1911. During the dedication speech, Roosevelt said that his administration’s two proudest achievements were the Reclamation Act and the Panama Canal.

In 1963, the Roosevelt Dam became a National Historic Landmark but withdrawn in 1999, the reason being the 1989 modifications had altered the original design’s integrity.

WEITERE GESCHICHTEN VON Rock&Gem Magazine

Rock&Gem Magazine

Rock&Gem Magazine

A New Amber Locality Fills a Gap

A sandstone quarry in central Ecuador has yielded the first significant deposit of Mesozoic amber from South America.

time to read

1 min

January / February 2026

Rock&Gem Magazine

Rock&Gem Magazine

Did "Left-Handed" Fish Leave Water Earlier than Thought?

Fossil evidence suggests that fish (or \"fishapods\") dragged themselves onto land during the middle Devonian Period.

time to read

1 min

January / February 2026

Rock&Gem Magazine

Rock&Gem Magazine

"Lab Quakes” Produce Surprising Results

When faults let loose and earthquakes result, the main effect we mortals experience is the violent shaking.

time to read

1 min

January / February 2026

Rock&Gem Magazine

Rock&Gem Magazine

This Egg is No Spring Chicken

How to date a dino egg

time to read

1 min

January / February 2026

Rock&Gem Magazine

Rock&Gem Magazine

Have we Already Mined the Critical Minerals We Need

Then why are we throwing them away?!

time to read

1 min

January / February 2026

Rock&Gem Magazine

Rock&Gem Magazine

One Toxic Worm

A critter that creates & tolerates orpiment!

time to read

1 min

January / February 2026

Rock&Gem Magazine

Rock&Gem Magazine

ROCK & GEM FIELD GUIDE: Silver

Silver (Ag) is a native element and one of Earth's most prized precious metals.

time to read

2 mins

January / February 2026

Rock&Gem Magazine

Rock&Gem Magazine

DINOSAURS OF THE HELL CREEK MUSEUM

In the Badlands of South Dakota, just outside the small town of Belle Fourche—pronounced “Bell Foosh”—a new attraction has taken shape that every dinosaur enthusiast should see. The Dinosaurs of the Hell Creek Museum is part hands-on exhibit, part science center and part active research lab.

time to read

3 mins

January / February 2026

Rock&Gem Magazine

Rock&Gem Magazine

The Lost Twins of Kongsberg

A Silver Story Resurfaced

time to read

3 mins

January / February 2026

Rock&Gem Magazine

Rock&Gem Magazine

Switzerland's ICE PALACE

Walk Inside a Glacier at The Top of Europe

time to read

7 mins

January / February 2026

Translate

Share

-
+

Change font size

Holiday offer front
Holiday offer back