Rock Collecting and Geology Basics
Geology is a fascinating field of study for many reasons. Not only are you studying the 4.5 billion year history of the Earth, but you are also studying the history of how the Earth has changed in that period. In the course of amassing a rock collection, you will find rocks that were around when dinosaurs roamed the Earth and seem to come from an alien planet.
Geology is also the study of phenomena like earthquakes, volcanoes, and floods. Each rock you collect is the process of billions of years of extreme forces.
If you’ve caught the Geology bug, starting a rock collection is an excellent place to begin. The best thing about it is that it’s an easy, inexpensive hobby, that you can start from anywhere in the world.
History of Geology
Geology as a subject dates only from the eighteenth century.
During this time, individuals searched for biblical evidence of the deluge, or Great Flood of Noah’s Ark fame. In looking for this evidence, collectors began finding fossils, which contained evidence of large creatures that no longer existed on the planet.
This piqued the curiosity of scientists, particularly during the Age of Enlightenment, a time when the traditional understanding of the world was being challenged.
In addition, a growing economic impetus toward mining led to a growing desire to understand minerals and the composition of the Earth.
As the Industrial Revolution took hold and large engineering projects, such as the digging of canals and building of railways began, geology became regarded as a vital science. Scientists began to understand much more about the Earth, including the presence of historical glaciers (the Ice Age) and changing sea levels.
The final major advancement in Geology came in the twentieth century with Alfred Wegener’s development of plate tectonics.
For the first time, geologists understood that plates moved across the surface of the planet, being subducted and colliding to form different types of rock and rock formations.
Contemporary geology now looks at the formation of rocks that come from space via comets, as well as analyzing craters on the moon. From its original starting point as an ‘Earth Science,’ geology is truly now a ‘Universe Science.’
Building a collection
If geology is a subject you’re interested in, then the first step is to start collecting rocks. The best thing about starting rock collection as a hobby is that it’s free, and you can do it from anywhere.
All you need is to collect different types of rocks and have some way of ordering them to discover their different origins. With a little bit of research and some considered cataloging, you can build a broad collection of fascinatingly different rocks.
Which Rocks to Collect
Which rocks you should collect is totally up to you. When you begin your collection – or if you are new to geology – you can start with something as simple as collecting rocks of different colors, or rocks that catch your eye.
When you go on a vacation or any trip to a new area try and collect a new rock (but make sure to follow the Code of Ethics, below). This will give you a great basis for your collection.
As you get better at cataloging, you will soon find where the gaps are in your collection and can take field trips to fill them in.
Where to find rocks
The best thing about starting a rock collection is that rocks are everywhere. Even rocks in your yard count and can be an excellent way to start a collection. However, once you’ve done that you can look at places where humans have cut into the earth. This is where rocks from below the surface will be found.
For example, quarries and construction sites often dig below the earth, and some may even have cut into the rock (which can be excellent for showing different layers of rock).
If you go on private property, be sure to ask for permission from the landowner and always be safe around construction sites.
It is for this same reason of checking near broken ground that the area surrounding your basement or home’s foundation is a great place to look as well. When that ground was disturbed to dig for the basement of the home you live in, it likely kicked up some interesting rocks.
Physically collecting a rock is a useful first step, although to have a successful collection you will need to catalog your items.
Cataloging means taking notes about the type and collection point of the rock, as well as other notes that may be useful in identifying it. The best time to do this is as soon as possible so that you don’t forget any details about where you got it from.
The two most common ways to catalog a rock are to paint on the rock itself, usually with a spot of white paint, before writing on it; or you can place the rock in a clear plastic bag and place a label on the outside of the bag.
On the rock or bag, give your rock a unique number or code, which will correspond to notes on an index card, a notebook, or on your computer.
On the index card, including the following information about the rock:
Where you found it
Who found it/whom you bought it from (plus price)
Formula (you can look this up online if you don’t know)
Any other interesting information
Code number (i.e. what you have written on the rock)
Size/weight of the specimen
Type of rock
When you found it
You could also include a photograph of the rock and add this to the index card. This will allow you to share the details of the rock without having to take it out of storage.
Collecting all this information will ensure you build an extremely useful collection and will increase the financial value of your collection if you ever decide to sell it. You will also be able to make connections between different types of rocks and the area that you got them from. The act of cataloging will mean that you learn more about the composition of the Earth – and ultimately that’s the whole point!
A ‘field trip’ refers to any journey or trip taking with the express intention of collecting rocks. Once you’ve begun your collection, and developed a cataloging system that works for you, you may need to travel further away to get new rocks.
This can be with the intention of discovering what’s around you or can be a deliberate attempt to find specific rock types.
As mentioned above, quarries and construction sites are good places to go on field trips because the surface of the earth has been disturbed, therefore allowing you access to rocks that are usually below the surface.
If you can get permission from the owner of the land, it’s usually best to visit on a weekend when there’s less likely to be work activity. When you are on a field trip you should always be considerate of safety and other people’s property.
The Code of Ethics (below) will make sure that rock collectors maintain the goodwill of the wider community and safety provisions will help keep you as safe as possible while you’re hunting for rocks.
Code of Ethics
Rock collecting has a clear code of ethics to make sure that those collecting rocks operate in a way that doesn’t denigrate the natural environment and engenders the most goodwill from property and landowners.
The State Geologist of Michigan endorses the following ethical code:
Respect all property, whether private or public. Always get the permission of the landowner before entering (and collecting)
Always respect laws, rules, and regulations in any area you are collecting
Do not use blasting materials or firearms to collect
Do not cause any damage to property you are collecting on
Leave the environment as you found it (including closing gates, removing any litter, and tidying the area you have been collecting)
Only build fires if necessary, and make sure they are fully extinguished (and do not leave any burning materials behind)
Do not contaminate any water supplies
Do not take more rocks than you need
Fully cooperate with any field trip leader
If you find any archaeological remains, fossils, meteorites or any unusual items, you should report your findings to a museum or your local university
Observe the ‘Golden Rule’ and make sure to leave the environment in the way you would want to find it
This Code of Ethics varies somewhat from country to country and state to state, although the basic principles hold, in that the general rule is to be as unobtrusive and as good a guest as possible. After all, geology is about a fascination with, and an appreciation for, the natural environment.
One of the best things about starting a rock collection is that you don’t need any specialist equipment to begin – you just need to head outside and start picking up rocks.
However, once you’ve exhausted this technique, you may have caught the bug for something a little more advanced.
In order to build your collection, you’ll potentially need some more equipment.
The following list is a good starting point. You might not require everything on the list (particularly if you’re budget-conscious), and you may be able to borrow these items or buy them used:
Crack hammer (2, 3, or 4 lb.)
Brush to clean specimens (a toothbrush will suffice)
Newspaper/ wrapping paper
You may also want to bring a field guide to help you identify rocks and minerals, although if you have a smartphone, you may be able to download a guide on to your phone. If you’re planning on testing rocks on site you may want to take items like a magnet, vinegar, or a UV lamp. However, you can always run these tests at home if you don’t want to carry too much.
Geology of your local area
One of the best ways to go from local collector to a more advanced level is to do some research into the geology of your local area. Most states have survey data and maps available to the public; research these and you’ll find something interesting about your local area.
This can be a great jumping-off point for a field trip. If your state has a large area of Jurassic rocks, for example, you can explore the area and see how it compares to your own area.
Find other geologists
One of the best resources for any new collector is the existing community. Rock collecting has an avid following online. People of all ages collect rocks and many will be happy to share their hobby with someone who’s as interested as they are.
An online search will help you find people who are rock collectors and to find out if there are local groups that hold meetups. Colleges and universities will have geology departments that will also be able to help you find out more about rock collecting.
Note: You should practice safety meeting anyone whom you have met online. Always meet in a public place and if you are under 18, take a responsible adult to accompany you.
Getting into rock collection is a great hobby – it’s cheap to start, there are materials everywhere, and you don’t need to travel to any exotic locations to practice your craft. Learning more about the world around you is always interesting, and you’ll soon start to know more about the history of the planet.
Once you start to build a rock collection, it’ll very quickly become addictive, and you may find that you’re constantly striving to collect the next rock.
Once you develop a system for classification you can continue your rock collection indefinitely – there’s no limit on the size of a collection or any age limits for rock collectors. So do a little research into the subject, read up on the code of ethics and the safety recommendations, and head out to start building up that rock collection.
Sources and Further Reading