From the tightly folded formations in the b>Appalachians across the broad reaches of horizontal sedimentary layers in the Allegheny Plateau, Pennsylvania's rocks record hundreds of millions of years of geologic history that tell an astounding story.
This book enables the reader to recognize the rocks and understand their meaning. It explains the landscapes of Pennsylvania in terms anyone can understand and enjoy.
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.
The Deluxe Moh's Hardness Pick Set now comes in two case types. The wooden case is small enough to carry and the top screws into the base to make a perfect desk stand. The plastic case is longer but the thinner size makes it easier to carry in your field tool set.Hardness is an important and quantifiable physical characteristic of a mineral and in your effort to identify an unknown mineral, the hardness, if known, combined with other properties, can narrow your search to just a handful of possibilities. Simply scratch a smooth surface of your unknown mineral with the picks of various indicated hardness. As an example, if a No. 5 pick scratches the mineral, but a No. 4 pick does not, then your mineral hardness is 4.5. Then compare this against a table of minerals listing hardness values to aid in identifying the unknown mineral.
Chisel edge rock hammers are typically used when you want to split layers of rock apart when looking for fossils.
|Head Width||7 inches|
|Overall Length||11 inches|
|Head Weight||24 ounces|
|Total Weight||1 pound 14 ounces|
New model. The sheath now has a "relaxed fit" making it easier to use in the field as well as working with more hammers.
Fits Estwing Pointed Tip Rock Hammers. Now fits the Estwing Supreme 24oz Big Face Pointed Tip Rock Hammer and the Valley Soft-Touch 20oz Pointed Tip Rock Hammer.
Leather snap case for the Estwing 24 oz, 22 oz, 13 oz, and 14 oz Rock Picks. Difficult to use until well broken in. We recommend the Gfeller Casemakers sheaths and holsters, especially the holsters. The Gfeller sheaths are sized better and their also pre-shaped to fit the hammers.
(I placed this on the site when the sheathshad a tight fit. It's still handy information." Hint: to make it easier to use this sheath use products like Vaseline, mink oil, saddle soap and even soap to help break it in. If you've recently broken in a baseball glove you may have some Rawlings Glovolium and Easton Glove oil around. Don't over do it. Do a web search on breaking in a baseball glove to find out how they do it.
I still don't recommend using the Estwing Leather Sheaths in any case. I sell them because some customers insist on having a sheath to protect things from the hammers. They're OK for storage but Amateur Geologist never carries one into the field. Use a holster.
Did I mention that these sheaths are just too difficult to use.
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