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Formation in Subduction Zones
Tiny diamonds have been found in rocks that are thought to have been subducted deep into the mantle by plate tectonic processes – then returned to the surface. (See Location 2 in the diagram at the top of the page.) Diamond formation in a subducting plate might occur as little as 50 miles (80 kilometers)…
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Formation in Earth’s Mantle
Geologists believe that the diamonds in all of Earth’s commercial diamond deposits were formed in the mantle and delivered to the surface by deep-source volcanic eruptions. These eruptions produce the kimberlite and lamproite pipes that are sought after by diamond prospectors. Most of these pipes do not contain diamond, or contain such a small amount of diamond…
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Methods of Diamond Formation
Many people believe that diamonds are formed from the metamorphism of coal. That idea continues to be the “how diamonds form” story in many science classrooms. Coal has rarely – if ever – played a role in the formation of diamonds. In fact, most diamonds that have been dated are much older than Earth’s first land plants…
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How Do Diamonds Form?
Diamond formation: Diamonds found at or near Earth’s surface have formed through four different processes. The plate tectonics cartoon above presents these four methods of diamond formation. Additional information about each of them can be found in the paragraphs and small cartoons below.
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What is Mineral Water?
Mineral water is something entirely different. Here the word “mineral” is used in reference to dissolved solids that occur in the water as it is taken from a natural source such as a spring. These dissolved substances occur in the water because while the water was in the ground it came into contact with mineral…
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Some Consider Water to be a Mineraloid
Water is not a mineral; however, it freezes into ice, which is a mineral. Some authors believe that water should be considered to be a “mineraloid,” a material that meets some of the requirements of being a mineral but falls short. Others disagree because they believe that a mineraloid only fails to meet the requirements…
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Is Ice a Mineral?
If we compare the properties of ice to the five requirements of the mineral definition, we find that it clearly meets the last four. However, requirement #1 presents a problem. A natural snowflake would be considered to be a mineral because it forms naturally in Earth’s atmosphere. However, an ice cube made in a refrigerator…
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Is Water a Mineral?
If we compare the properties of water to the five requirements of the mineral definition, we find that it fails to qualify as a mineral. Water is a liquid, so it does not meet requirement #3 – being a solid. However, at temperatures below 32 degrees Fahrenheit or 0 degrees Celsius, water becomes the solid…
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What is a Mineral?
The word “mineral” is used by geologists for a group of naturally occurring crystalline substances. Gold, pyrite, quartz, calcite, and fluorite are all examples of “minerals.” To be a mineral a substance must meet five requirements:
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Herkimer Diamond Specimens & Jewelry
Why hunt for “Herkimer diamonds”? It’s great fun and every time you break open a rock you will look with anticipation to see if you liberated an unseen quartz crystal. Nice “Herkimer diamonds” are highly prized mineral specimens and are sought by mineral collectors worldwide. Large numbers of Herkimer crystals are also used in jewelry…