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What is the NCMA all about?

What are some of the NCMA events?

What is micromounting?

What do I need to get started?

How do I join?

Galkhaite, Getchell Mine, NV

 

What is the NCMA all about?

At the NCMA Annual Meeting

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The NCMA is a group dedicated to the study of microminerals.  Our 70 plus members are a diverse group of individuals who span the entire range of mineral expertise, from the casual collector to the geological professional.  Some of our members enjoy the artistry and perfection of microminerals. Others enjoy getting out in the wilderness to collect minerals.  Still others are interested in the technical aspects of mineralogy and the never ending search for the next new mineral.  Some people just like to gather with their friends and socialize.

 

What are some of the NCMA events?

Once per year, the NCMA sponsors a 3-day symposium in El Dorado, CA. Members gather from all over the United States to meet their friends and share the year's finds.  A bountiful giveaway table ensures that everyone has an opportunity to enhance their collection.  In addition to the minerals, the NCMA brings in speakers from around the world to lecture on the latest geologic and mineralogical topics.  There are also mineral slide shows, demonstrations, and a mineral auction.

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The giveaway table

 

 

What is micromounting?

 Types of mounts

So what is micromounting anyway and why does that very question elicit debate? The answer is, that there are many ways to mount microminerals. This results in a lot of friendly debate about what the best methods are and what constitutes a "proper" mount.

 

In the broadest sense however, I think Neal Yedlin said it best:

 

 Mount anything that you want, provided it falls within the limits (how we dislike that word) defining a micromount - a natural mineral, in crystals, mounted, labeled, requiring magnification for proper viewing.   -- Neal Yedlin

 

Generally, a modern micromount has come to mean a carefully trimmed micromineral specimen that is permanently affixed for best viewing, mounted inside a plastic box measuring approximately 1" x 1". The mount is labeled with a minimum of the mineral name (species) and the collection locality.  Variations within this theme are endless however, and there is a lot of artistry and ingenuity that goes into the process.  This is why some people enjoy collecting the micromounts just as much as the minerals themselves.

The bottom line is this:  if you are going to seriously collect and study microminerals, you need a method of preserving your miniature masterpieces and you also need a way of properly labeling your specimens so that they are of future value not only to yourself, but possibly, generations to come.  Micromounting is one way to achieve this, but is by no means, the only method.

 

Yedlin micromount

 

For those interested in learning more about micromounting, here are two excellent references (both out of print) that you may be able to get your hands on at your local library or university:

SPECKELS, M.L. (1965)The Complete Guide to Micromounts. Gembooks, Mentone, California, 97 p.

WIGHT, Q. (1993)The Complete Book of Micromounting.  The Mineralogical Record, Tuscon, Arizona, 283 p.

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What do I need to get started?

 Hastings 10 X Triplet

 

       [ Hand Lenses ] [ Microscopes ] [ Illuminators ]

  • An unquenchable thirst for knowledge?
  • 2 loose gears and nothing better to do?

Although the latter would certainly be beneficial, what you really need is a good hand lens to get going.  The tool of choice is the 10X Hastings Triplet, meaning that this hand lens has a 3-lens system which corrects for spherical distortion and chromatic aberration.  A lanyard worn around the neck, is a good idea to keep your lens from getting lost, because these things are definitely not cheap: typically $30.00 to $50.00.  Well cared for however, you can consider this a lifetime investment.  Good hand lenses are available from every geological supply, rock shop, and scientific supply.  Here are just a few sources:

 

Once you really get bitten by the bug though, it's time to start thinking about investing in a microscope and an illuminator.

Microscopes

The microscope used for this type of work is the stereo low-power microscope. Unlike a high-power biological microscope, these microscopes have a relatively large working distance and excellent depth of field, which are both necessary attributes for the viewing of 3-dimensional mineral samples.  These microscopes generally come in two varieties, fixed magnification and continuous zoom.

Stereozoom 4 scope and Dolan Jenner illuminator

 

Fixed Magnification Scopes

  • Magnification switched between 2 or more values by means of a rotating selector
  • Typical magnification values of 10X and 30X (good for 90% of micromineral work)
  • Magnification can be increased by changing the eyepieces (good for that other 10%)
  • Used scopes start at about $200.00 (U.S.)

In the last few years, Russian scopes have become available on the market.  Although simple in construction, they have a 5 position turret that delivers magnification values between 7.5X and 100X.  These scopes have good quality optics and range in price between $300 and $800 new, depending on accessories.

Zoom Scopes

  • Continuous magnification adjustment throughout range by turning a knob
  • Generally higher quality optics than fixed magnification scopes, rendering higher resolving capability
  • New scopes priced $1200 and up
  • Used scopes priced $500 and up
  • Stereozoom 4, manufactured by American Optical, Bausch & Lomb, Leitz, or Leica, is the most common model (0.7X to 30X)

Shopping for a scope

  1. Talk to other micromineral enthusiasts
  2. Check the local classifieds
  3. Check the used microscope dealers
  4. Check out the new equipment dealers

If you do decide to purchase a used scope and you really don't know a lot about them, it would be a good idea to have someone with some experience check it out for you.  Although when well cared for, a microscope will last a lifetime, there is also some pretty badly abused and unsalvageable equipment out there.

Illuminators

Most beginners tend to put all of their money into the microscope and they totally forget about lighting.  However, the image viewed under a microscope is only as good as the lighting.  Some microscopes come with built-in above stage illuminators.....forget it.....you would have better luck with a candle!

Tensor Light

Most people on a budget usually start out with some variation on the conventional Tensor or halogen lamp.  These can work pretty well, but unfortunately the light source and thus, the heat source, is right next to your microscope.  The result of this proximity can be burnt fingers, melted or destroyed specimens, and in some cases, melted microscope parts.

Condenser style

The next step up the ladder is the condenser type microscope illuminator, which uses a set of lenses to focus the beam of light.  These illuminators can set further back from the work area and still provide adequate illumination for viewing.  One typical model is made by American Optical, which sells for about $250.

Fiber optic

The most desirable style of microscope illuminator is the fiber optic illuminator.  These high powered illuminators place the light source well away from the work area and transmit light to the subject by means of one or more, flexible, fiber optic conduits.  Accessory lenses can be placed on the end of the fiber optic conduit to provide focusing of the light beam.  These units are not cheap.  A typical fiber optic illuminator tends to cost $350 and up, complete.  One advantage of these units is that they can double as a photographic light source; particularly, the bifurcated (2-conduit) illuminator.

Edmund Scientific and CGS are two potential sources of microscope illuminators.

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How do I join?

 Emma

Everyone likes microminerals!

 

Membership in the NCMA is a bargain, at only $10.00 per year, per person, or $15.00 for couples.  Your modest membership fee covers the cost of our NCMA newsletter, keeping you abreast of all group activities.  .

 

  • Annual Dues
    • $10.00 single membership
    • $15.00 couples membership
  • Annual Symposium Registration Fee
    • $20.00 per person for all 3 days (pre-registration rate, $25.00 at the door)

For more information about joining the NCMA, contact the NCMA Treasurer, Theresa Kokinos:


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Last Updated: 03-14-2016 Address Comments to:
elc@minresco.com

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