Find More Agates: Insider Tips on Finding Agates ANYWHERE
Agates! One of the easiest and most common rocks on a rockhounds mind!
What is a "Rockhound", they are someone who looks for rocks everywhere they go like a bloodhound on the trail! You can find many cool rocks just about everywhere you go in the Pacific Northwest but one of the most prized is our amazing abundance of AGATES!
What is an Agate?
Well, like many common names many agates will fit this general description but not ALL of them, why? Different geographic regions have different definitions of what an agate is.
All of them mean that the stone is made from cryptocrystalline or microcrystalline quartz from crystal formations too small to be seen with the naked eye.
All of them mean they were formed when silica dissolved in water, left the water behind to become a stone, the water may have evaporated or flowed on.
All agates will be around a 7 on the Mohs scale of hardness as a quartz family mineral. That means they cannot be scratched with a pocket knife. Also agates will, most of the time, demonstrate a conchoidal fracture when broken. That means that it breaks with a shell-like fracture. Many agates that looks like someone smushed their fingernail into it many many times and sometimes it will look like how glass breaks. To be an agate, most people will insist that the stone shows light through it when sliced but not necessarily whole.
Some agates have such densely packed inclusions like moss or plume that it makes the stone appear opaque until sliced and backlit with a light.
Agates form in a wide range environments. from cracks and bubbles in another stone to layers of thick agate from forming in a hotspring or hot water deposit. One thing about agates is that they form near the surface in a geologically "cool" (under 200 degrees celsius) environment. Agates are considered a sedimentary stone.
Where the jury is out: Some people will be very passionate that an agate must have some kind of inclusion or pattern to be an agate otherwise it's just plain chalcedony (cal-said-knee) and not an agate. This is a common argument made by Lake Superior agate hunters and the agate hunters of the Dakotas. We will call just about anything translucent and cryptocrystalline or microcrystalline quartz an agate in the Pacific Northwest.
Why do we have so many agates to find in the Pacific Northwest? We have or have had a lot of two of the most important things needed to form an agate: water and silica. Both cool surface water carrying silica can make an agate as can hot but not too hot water heated by underground magma and every imaginable scenario in between.
In ancient alkali lakes, silica will seek out more silica and form blobs slowly dehydrating as the lakes ages and dries out. This is how snake skin agate nodules found near Rome Oregon were formed.
Some sodium sure helps too, gets that silica moving around! In fact if you find an agate at the beach or in an old alkaline lake bed and it has white "stuff" on it, it's sodium silicate, essentially a salty opal layer.
Ok, so how do we find more agates?
- Sunlight: As our days get longer it's a perfect time to take advantage of any sunlight available to you! When you come upon rocks where you might find agates, try to put them between you and the sun in all environments. Being that a classic tell tale sign of a stone being agate is that it is translucent however you can't always tell because of "surface weathering" or staining.
- Weathering: Water is KEY to the formation of agates and will leave some tell tale signs its been present. Its also why mountains get shorter. Many times the tops of hills and ridges will be littered with the stronger material like agates and other quartz family minerals. Water also rots rocks so if you are by a road cut or quarry or other area with exposed rock, look for where there might be minerals forming and rotten rock.
- Right Geology/Right Place: Learning how to read a geologic map is invaluable however it won't tell you all the secrets. I suggest going to some known agate beds like the Maury Mountain Moss Agate Beds, the Central Oregon Coast and/or other well known agate locations in the Pacific NW and NOTICE what kind of soil you find agates in. What color is it? Consistency? Geologic age? Once you learn to recognize these patterns you will be ready to explore for your own new locations. There are some great books out there right now which will give you known locations or join me for a Beachcombing Explorience for a hands on hunt with me on the Central Oregon Coast!
On the beach agates, plastic and shells are most likely to glow in the light. I always pick up the plastic and if its an agate I like to "high grade" them right away and decide if its one that will bring me joy, that way I can leave the ones which don't for others to find.
In a creek or river find the gravel bars and treat them the same way you would on a beach, look for the translucent stones with the help of light refraction and sunshine. Always check local fish protection laws before rockhounding in a creek or river, rockhounding can disturb salmon habitat.
In the desert on in a prairie it's a little different, there's no water! What do you do? Look for where water used to move or moves in storms. Scree or rock fall areas can be a treasure trove of agates. Walk draws and dry creek beds. Once you find some you can start to venture outside the draw to find the source. The tops of ridges can be treasure chests if you can get to them.
Looking in the forest is very similar to looking in the desert but even harder because of all the beautiful trees. Once again look for where water is moving or has moved. Imagine where creeks used to be or how big they used to be. Tree roots can capture and trap rocks in them, fallen trees can have agates stuck in their roots. Some people will "probe" for agates, using a steel rod to tap rocks below the surface of the forest floor listening for the tell tale "tink tink" of a higher silica rock.
Collecting agates is a fun and rewarding hobby for people of all ages, from young to old. You don't need to know what exactly the stone is to have it bring you joy so don't get too caught up on what you have found, just if you love it or not.
Not sure if you have an agate? Email me at email@example.com with still pictures in natural light and a backlit picture and I will try to help you! Thank you for reading our blog! for more information on the Beachcombing Explorience visit: https://www.rockyourworldgems.com/pages/lincoln-city-beachcombing-exploriance