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Mined from pegmatites,gems and rare minerals
Muscovite,beryl and amazonite
Whats a pegmatite?
This is a question I am often asked while talking about mineral collecting.What is a pegmatite?
My simple answer is a light colored rock formation which consist of large crystals of feldspar,quartz and mica.But that is a simple explanation of a common pegmatite and pegmatites can be far from common in many cases.So even in a common pegmatite there is feldspar,quartz and mica,still simple until you understand the feldspar may be microcline,albite,orthoclase or any of the other feldspar minerals.the quartz may be rose,smokey,milky or clear.The mica may be muscovite,biotite or lepidlite to name a few from that group.So you could have nice crystals of microcline or colorful gem amazonite from the feldspar group.Clear text book crystals of quartz or gem rose quartz from that group.And the mica could be pink lepidolite or green muscovite to name a few minerals from the micas.even in a common pegmatite there can be minerals,crystals and gemstones to collect.
A more detailed explanation of a pegmatite is this.A pegmatite is of the igneous rock group.It consist of feldspar,quartz and mica and the crystals are large in size.Still a somewhat simple explanation of what can be very complex.Some pegmatites have high concentrations of trace minerals and they can have gems and rare minerals in quantity in them.Lithium,beryllium,cesium,tantalum,boron and uranium as well as other trace elements can be found in quantity in some pegmatites.Rare minerals and gems like beryl,spodumene,tantalite,uraninite are found in some pegmatites.Gems like aquamarine,topaz,garnets,kunzite are the result of high concentrations of trace elements.
Note:The largest crystals of many minerals have been found in pegmatites.
So pegmatites are a great place to go mining for minerals,crystals and gemstones.I have many crystals,gems and rare minerals in my personal collection which i found in pegmatites.They are an important part of our modern world.This is as simple as I can put it to you.Alas pegmatites are beyond what is simple and are beyond my simple explanation.
Aquamarine Gem Quarry Mine Albany Maine
Gems in Pegmatites
Pegmatites have long been mined for the minerals found in them.Here in the northeast the history of mining pegmatites goes back to early 1800's with muscovite mica being the mineral of interest.Muscovite was used as a glass substitute in woodstove and many people still recall isinglass mine or Isinglass Mountain.Today there are several gem mining operations in Maine and New England.Gem aquamarine and gem tourmaline being the main mineral of interest.Worldwide pegmatites are mined for gems of all kinds.emerald,topaz,tourmaline,ruby and sapphire ect...There are important minerals mined for lithium, tin, tungsten and the rare earth metals.
Black Tourmaline Crystals
Gems and Minerals
As you can see many rare gems and valuable minerals are found in pegmatites.Old mines still hold new discoveries and new discoveries are being found.Pegmatites have supplied ore minerals,gemstones and minerals for thousands of years.And there are many new discoveries waiting to be found.So whats a pegmatite?Its a treasure to those who know.A pleasure for an old field collector like myself.A wounder to a child when they find their first crystal.And a girls best friend,even if she does not know where her gemstone came from!
Mt Mica Mine Paris Maine
A gem mine in Paris Maine
Hunting for Gemstones
- Mineralogy Database - Mineral Collecting, Localities, Mineral Photos and Data
The web's most comprehensive and regularly updated mineralogy database with information on minerals from around the world and thousands of photos
- Vermont Geological Survey home page
Geology and Mineral Resources Division - Vermont Geologic Survey- aid and advice, researches Vermont geology, resources, and topography, creates maps, archives information for the public, low-level radioactive waste disposal,part of the Department of
New York Geology
- New York State Geological Survey:unofficial gateway
The unofficial gateway to the resources of the New York State Geological Survey
- Diamond Mines - Crater of Diamonds State Park
Visit Crater of Diamonds State Park, where you can dig for diamonds, learn about the history of diamond mines, see Arkansas wildlife and much more at the worlds only diamond-producing site open to the public.