Here are the names for the different sizes that I use as "standards".

MINERAL SPECIMEN SIZES

by Eric Greene

Sizes of specimens

Some, but not many of us mineral collectors are blessed with unlimited space to display and store our mineral collections. Even in our 13-room house, we don't have space for everthing (and Jeanne has a rule: no mineral specimens in the part of the house we live in!). So, like other factors to consider in building a mineral collection (color, quality, species, locality, etc.), size does matter, and collectors must think about what size they want to collect. For example, consider this: you can display 1,000 thumbnail-sized specimens in the the space required to keep 50 hand-sized specimens. That certainly puts it in perspective!

Here are the names for the different sizes that I use as "standards". Many collectors use just four of these terms (thumbnail, miniature, small cabinet, cabinet): 

Thumbnail specimens (1")
If a specimen will fit inside a 1-1/4" cubic plastic box, it is called a thumbnail specimen (T/N for short). These little plastic boxes are called "perky" boxes, after their inventor, Willar Perkins. A thumbnail specimen is usually less than 1" square.

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Toenail specimens (1.25")
This term was coined for a new division in Tucson judging. Basically, if a toenail specien is a little too big to fit in a thumbnail box, but is smaller than a miniature specimen.

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Miniature specimens (1.5"-2")
The next size up is a miniature. This size fits inside of a 2" or 2-1/2" cubic plastic box.

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Small Cabinet specimens (2"-3")

A small cabinet specimeen is in between a miniature and a cabinet-sized specimen. It is sometimes called a hand specimen, since you can hold it in your palm. If it's too big to fit in the 2" plastic box, but not as large as an apple, then it is a small cabinet specimen.

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Cabinet specimens (3"-4")
If it's bigger than and apple, but not as big as a grapefruit, then it's a cabinet specimen. Larger than that is too big to easily put in your house. 

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Large Cabinet specimens (4"-6")
If they are grapefruite size or larger (over 4"), and you can still pick it up and put it on a shelf in your cabinet, then I call these large cabinet specimen.

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Museum specimens (>6")
Anything bigger than a large grapefruite deserves to be in a museum.

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Micromounts
Mineral specimens that require the use of a microscope to view the crystals are called micromounts (M/M for short). These are typically the size of your pinky nail or smaller. They are usually mounted in a small cardboard or plastic box with a lid to keep dust off the crystals.

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