How To Make A Mohs Test Kit and Kit Reviews
The case of unidentified rocks – the rockhounds nemesis. There is nothing better than a good day outdoors rockhounding. Well at least I think so. Being the first to see/touch a mineral that formed millions of years ago is amazing.
Identifying what you find can be a tricky business. Field guides are available with tons of images to help. Sure you may have an arsenal of knowledge of what to look for but having a Mohs test kit handy can make the job easier.
Knowing how hard minerals are is part of the identification process. Getting a handle on the mohs scale will be part of the battle. The mohs scale of hardness is the relative hardness of minerals from softest to hardest.
Get to know the 10 common minerals on the Mohs scale. This will give a good foundation for mineral identification. Finding the hardness of your mineral is as easy as a simple scratch test.
I have a more in depth article and guide to the Mohs scale here.
A few key points to remember
Softer minerals can not scratch harder minerals
Some common objects will suffice for scratching till around 7 on the scale which is quartz.
Each mineral on the scale can scratch everything below it from hardest to softest.
The first thing to scratch your mineral with is your finger nail which ranks at a 2.5 on the Mohs scale.
Check out this video for a good representation of the scratch test.
Below are tips on how to make your own Mohs test kit and a few reviews if you are planning on buying one instead.
How To Make A Mohs Test Kit
A few common items will go a long way when testing mineral hardness.
- Your finger nail (hope thats a no brainer at this point)
- Copper penny
- Steel File
- Pocket Knife
These are easy enough to keep in your pocket. Hopefully you can keep your fingernail attached to your finger. Although digging up minerals can cause some damage to the hands, for all intents and purposes there is no need to carry your finger nail around in your pocket.
Another option is to go rockhound or buy all the minerals on the mohs scale. Keep them in a small divided container. Easy enough to carry around if you keep the specimens small.
If you are looking to make the job a little easier you can purchase one of the options below.
A kit to keep at home and a kit to keep in your vehicle is not a bad idea.
3 Mohs Test Kits Worth Considering
This is a box of all ten minerals labeled by number. This particular mohs test kit comes with a very tiny diamond. This is a basic and traditional mohs kit. This is a good kit to keep around the house or where ever you keep your collection. Great for teaching others.
This mohs test kit has a little more to it minus the diamond. You get more to work with as far as your scratch testing. This kit includes nine minerals from talc to corundum, streak plate (for checking the streak color also important in identification) glass plate, and a nail. I prefer this kit over the above mentioned because your really don’t need a diamond. Having the small glass plate and streak plate readily available with this kit are nice additions.
This is a sleek desk top mineral testing kit. This is a unique set as the hardness points on the picks are not the actual minerals but alloys and metals made to replicate the hardness of the mohs scale.
The set comes with four double sided testing picks from hardness two through nine. It also comes with a streak plate, glass plate, and a magnet. A nice thing about this kit is that the pick tips can be reshaped or replaced so it will withstand wear and tear better than actual mineral specimens.
The set comes in a nice wooden desktop case. This makes a great gift for rock enthusiasts and geologists.