History’s Gem of the Month: Hints on Hunting and Finding Agates

 September 2009

While looking through the museum’s archives, I found this article drafted by the museum founder, Axel Niemi. I’m not sure if he ever published the article, but it is worthy of inclusion as this month’s history gem. I’ve also added a few pointers, so actually this is a joint article written by Axel and me.

Hints on Hunting and Finding Agates
By Axel Niemi and Karen Brzys

Michigan’s Eastern Upper Peninsula (Alger, Luce, and Chippewa Counties) is home to unique agate and jasper rocks. For the past 30 years, the author has picked pretty objects called quartz family minerals. This article presents an interesting view on how you, too, can assemble a collection of unique quartz treasures.

This Eastern Upper Peninsula of Michigan is covered for the most part by enormous sand-gravel-clay deposits. Few areas have yielded so wide a variety of quartz minerals, as well as other rocks. Few areas also show such promise of steady and continuous yields. Each year, ice bergs break off shore, move around the lake, get pushed up onto distant beaches, collect rocks from that beach, break free only to get pushed by northwest winds to their final resting spot on the beaches in the Eastern Upper Peninsula to melt and dump their loads. After 8,000 years of this happening, our local beaches truly are a melting pot of all the rocks found around the lake, as well as a new supply of agates each year. This combined with the till deposits left by the glaciers makes our local beaches a rockhounders paradise.

Many friends have examined the multiple varieties of agate and related quartz minerals on display in my agate shop. After telling them they that the specimens had come from gravel-sand deposits within a few hour’s to a few minute’s ride, I have sometimes been called a liar. Yes, although my success has resulted from patience and many hours of searching, I admit to the difficulties encountered in hunting these all but camouflaged mineral stones.

The difficulty in finding these gravel deposited elusives, arises in keeping one’s mind on finding not one but any of the host of varieties of quartz minerals. The average picker would be quite happy to find a nice banded agate or red carnelian. After examining what I had picked and finding them beautiful, tourist friends say they had thrown oh so many good specimens away. This I have learned is unlikely. One of the faults of most beach combers is that they are ignorant of the existence of these quartz treasures, and they usually cannot tell the difference between the different types of quartz rocks. Another challenge to looking for quartz minerals is the tremendous amount of tiny powdery fractures that camouflage the true nature of the mineral. Finally, while on the beach you are challenged by the fact that very few agates are scattered amongst billions of other iron-bearing red rocks and want-a-be agates. To be successful, you must be prepared to pick up and examine all the possible quartz minerals, while trying to avoid being distracted by other pretty rocks.

Agate hunting is a real challenge to those with good eye sight, and not recommended for those with eye defects. Of course, those with eye problems may have to resort to sitting and digging, rather than walking erect – which usually allows you to examine a larger quantity of rocks. As more and more pickers hit the beach, the supply of agates and related quartz specimens will be impacted. However, the wave-water action as well as moving ice will continually move the piles of rocks, wear new material into view, or transport new rocks to the Grand Marais beaches each year.

The area that is best for looking for agates runs from Au Sable Point in Alger County, across the northern edge of Luce County, to Whitefish Point in Chippewa County. This stretch of beach contains some areas that have easy access by car, as well as some remote sections not often explored.

The tips on how to successfully find agates are listed below.

  1. Walk and look, scanning the rock piles as thoroughly as possible.
  2. Look closely at every stone. You never know which one is the agate treasure.
  3. Practice, practice, practice. At first, your neck, leg, and back muscles will be sore and tired. The more you look for agates, the more your body will be up to the task.
  4. Read books and acquire samples of agates so that you know what you are looking for.
  5. Look near the very edge of the water. The water will help accentuate the banding.
  6. Also look in the dry rock. When dry, the shiny waxy luster and the conchoidal fractures will be more apparent.
  7. If you have hip boots or are willing to walk in the water, it is possible to spot agates – but the water must be calm. Also, agates are denser than other rocks and sometimes they tend to work their way below the surface of the rock piles located out in the water.
  8. If there are multiple rows of rocks on the beach, left over from surf with various wave heights, look for the related gold cherts and red jaspers. They are also microcrystalline quartz with the same density as agates. Thus, as the waves return back down the slope, agates, cherts, and jaspers will “fall out” of the wave at the same time.
  9. Look where others have not looked. The farthest you walk from road access the better.
  10. Be the first on the beach after a storm. This is when the gravel is moved around exposing new material.
  11. Do not cover too much territory too fast. It is better to look over one section carefully. Nothing pays off better than careful looking. Sometimes I’ll even walk over the same section 3-4 times, only to be rewarded by finding an agate that was previously missed.
  12. Concentrate on picking up only agates and other quartz rocks. Avoid the pretty rock syndrome. Let’s say you pick up 500 rocks in an afternoon of looking. If 400 of those are just pretty rocks that are obviously not agates, then you have only a 1 in 100 chance of finding an agate. If all 500 of the rocks you pick up are agates or want-a-be agates, you have a much higher chance of being successful.
  13. When you see an agate candidate – you must pick it up; even if your back tells you that you don’t want to bend down. Of course, the use of an agate scoop can also help. For what ever reason, the obvious banded sections of specimens are very often facing down, out of view. Thus, if you don’t pick up the rock, you may miss that it is an agate.
  14. Most agates have some apparent banding showing, or have some translucency. Usually if you are not sure it is an agate – it is not.
  15. Use proper protection for your eyes, such as a Visor cap. Although some may have success wearing sunglasses, I find that it is harder to spot agates while doing so.
  16. Use a bright flashlight, or carefully use the sun, to check specimens with backlighting. Sometimes backlighting will expose banding that you cannot otherwise see.
  17. Walk toward the sun (east in the morning and west in the evening). The translucency of agates will cause them to “glow” at you.

Some of the mineral treasures you can find on the beach, in addition to banded agate, include: red jasper, banded jasper, gold silicified fossils, banded chert, red translucent carnelian, water-level onyx agates, eye agates, sagenite agates, moss agates, tube agates, and shadow agates. You can also find some red, pink, and green unakite, limestone fossils, and feldspar.

Happy Rockhounding!

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