Much more than a fee mining guide, this unique book is a treasure trove of
interesting sites to see and things to do related to rocks & minerals,
gemstones, crystals, fossils, gold, and other treasures.
Whether you are an experienced rockhound or prospector, or a family on vacation,
you'll find fun, adventure, and maybe precious gems, gold, or hidden treasures
of man or nature.
Organized by state, site information includes seasons and times of operation,
address and contact information, cost, tools and supplies needed. Interesting
history, regional attractions and camping information help to make your trip
even more enjoyable.
Includes Sites in: Alabama, Arkansas, Connecticut, Delaware, Florida, Georgia,
Illinois, Indiana, Iowa, Kentucky, Louisiana, Main, Maryland, Massachusetts,
Michigan, Minnesota, Mississippi, Missouri, New Hampshire, New Jersey, New
York, North Carolina, Ohio,Pennsylvania, Rhode Island, South Carolina, Tennessee,
Vermont, Virginia, West Virginia, and Wisconsin.
Cover: Paperback; Size: 8 1/2 by 11 in; Pages: 264; Published: 2010
The BelOMO 20x Quadruplet Loupe Magnifier has a viewing area of .28" (7mm), much larger than the Bausch & Lomb Hastings 20x Triplet Magnifier. The large .5" (17.5mm) 4 elements gather lots of light to provide this quadruplet loupe with a bright and clear view.
The following details are true of any lens such as a loupe magnifier, microscope, telescope, camera lens or other high magnification lens.
A 20x magnifier should NOT be the only magnifier you own. It's just too much magnification for normal usage. For instance, if you're using it to look at newsprint you would see at most a 4 letters at a time.
Must you have such strong magnification?
You'll be incredibly close to the object you are examining. Almost touching. For a 10x the focus distance is around 3/4'' but for a 20x it's about 5/16''.
The 20x power magnification provides a very strong level of
magnification which works best on flat objects like coins or stamps or surfaces of objects.
However, only a small area (field of view) will be visible. Think of examining a quarter and all you can see is the date but it's highly magnified.
The stronger the magnification means the less depth of field the lens will have. Depth of field is the vertical relief that appears in focus on an object having an irregular surface like a rock or mineral. You'll have to ''dance'' the lens around more on rocks and minerals but the portion of the object you're viewing will be highly magnified. The limited depth of field also make a 20x the most magnification you'll want to use when hand holding a loupe. With a higher magnification the slightest movement in you hand will cause the image to continually move in and out of focus.The high magnification works well when you need to closely examine the surface of a rock or mineral, the surface of a gem for minute scratches, small areas of coins and stamps or any other object where you need to examine a small area under high magnification. It's great for reading laser inscriptions on diamonds.
The larger size of this lens compared to other 20x loupes means it will capture lots of light for a very bright view. This is also a loupe that you can hold comfortably in your hand unlike the smaller than a dime lens from Bausch & Lomb.
The housing and cover are machined metal and coated with a matte black finish and assembled using flathead screws. Belarusian Optical and Mechanical Association (BelOMA), makers of sights for guided weaponry, camera lenses, and other optical components manufacturers these loupes.
Highly recommended by the Amateur Geologist. The BelOMO loupes are the loupes we always use though it's the 10x that we typically carry in the field. If you MUST have 20x power then this is a great lens to have.
Don't let this price fool you. The BelOMO loupe is a FANTASTIC buy. These are quality lenses that stand on their own against the higher priced competition. Take advantage of the recovering Belarus economy and a military supplier finding other revenue streams in a capitalistic market.
Each BelOMO loupe we ship is custom treated to prevent the screws from coming loose with usage.
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