NREC Online Lesson - Rocks and Minerals in Nova Scotia
To begin this lesson we must first make a clear distinction between rocks and minerals.
Question: What is the difference between rocks and minerals?
Answer: Minerals are pure substances whereas rocks are made up of many different types of minerals. So basically rocks are minerals.
There are many different types of minerals including salt, gypsum, coal, iron, oil and gas, tin, etc. These minerals are important because we use them every day. Just look around the classroom , you may find examples of these - gyproc on the walls, tables and chairs sometimes have metal parts, the nails used to build the structure of the building, even the glossy coating on magazine pages comes from a mineral. Perhaps the students are bussed to school which is a situation where there are many minerals used form the metal of the bus to the gasoline it uses.
If minerals are used every day, then students may think we have lots of them.
Question: Why must we be careful with the sources of our minerals?
Answer: Minerals are a non-renewable resource. This means that once we have used up the supply, it is gone. We can not plant diamonds or gold and expect it to grow like we can with trees. This is why we say " if it can't be grown, it has to be mined".
Since minerals are located in the ground then there must be some way of locating these minerals.
Question: Who locates these minerals?
Answer: A Geologist
What does a Geologist look like? (ask the students to draw a picture of what they think a Geologist might look like on the Geologist Worksheet. It can include their dress, associated tools, etc.
Question: What does a Geologist do?
Answer: We know they look for minerals but is there anything else? A Geologist can be involved in many different types of projects including: looking for fossils, looking for minerals and mineral-bearing rocks, teaching, mining, environmental work, i.e., land reclamation, research, etc.
In order for a Geologist to do their work, they require special tools.
Question: What tools would a Geologist need or use? (if you have examples of these, you can place them in a nap-sack and have the students pull one item out at a time. Review each item with a brief explanation of its' relevance to a Geologists' work.
- Compass: Used for navigation in the field. Used to see if rock samples are magnetized (the compass needle would react).
- Flagging Tape: Used to mark an area where samples were found so that if necessary, they could return to it at a later date and it would be easier to locate. Flagging tape can be written on, so information, i.e., sample numbers, can be written directly on it.
- Magnet: Used to test if the rock contains metallic substances.
- Acid: By placing only a few drops of diluted acid (HCI) on a rock, we can test for the presence of limestone. If there is an obvious reaction, then limestone must be present in the sample.
- Binoculars: Used to look over long distances to scout an area. People wouldn't want to walk over long distances to an area where there is nothing, when they could have gone a different direction and found a deposit of minerals.
- Streak Plate: This is a small ceramic tile. Because ceramic is very hard it helps a Geologist determine if the rock is hard or soft. As well, by looking at the color of the streak that is left you may be able to discover characteristics about the rock (i.e., metallic, gypsum, smaller particles within the rock, etc.)
- Camera: To take pictures of the samples.
- Scale Card: Geologists do not want to misrepresent the size of the samples, crystals, etc., that they may discover so by placing the scale card (which has a ruler on the side) next to the sample, they eliminate this misrepresentation. The scale card gives a person looking at the picture a reference that is familiar to them that they can judge the true size of the object they are looking at.
- Survival Kit: Anyone out walking in the woods or wilderness should carry a survival kit.
- First Aid Kit: Should be included with a good survival kit.
- Sample Bags: Any type of bag may be used to collect samples in, to bring back with them for further testing and positive identification.
- Geologist's Hammer: To chip away at rocks when collecting samples. A Geologists' hammer is constructed of specially hardened steel to prevent steel flakes from flying when they are chipping at a rock.
- Safety Glasses: When chipping away at rocks, dust and debris may fly. The glasses will protect a Geologist's eyes from any particles in the air. As well, if you hit a rock that is harder than you hammer may shatter. This is why we should never hit rocks with a hammer.
- Pen & Notebook: To record information such as descriptions of where the samples were collected.
- Magnifying Glass: To get an up close look at samples to see what the combinations may be of minerals within the rock.
- Nail: By using this piece of equipment you can scratch a rock to test the hardness, If a mark is left on a rock then we know that the material is not a hard as a nail.