Hello, my name's Ms. Niven, and today we're going to be looking at rocks and minerals as part of our unit on earth's resources.

Now, you may have some experience of what we talk about in today's lesson from your previous learning, but what we do today will help us to better understand and answer that big question of how can we explain changes that we see in the air, the oceans, and the land.

So by the end of today's lesson, you should feel more confident being able to describe the differences between rocks and minerals.

Throughout the lesson, I'll be referring to some keywords, and these include mineral, crystalline, and rock.

Now the definitions for these keywords are given in sentence form on the next slide, and you may wish to pause the video here so you can read through them or make a note of them to refer later on in this lesson or later on in your learning.

Today's lesson is broken into two parts.

We'll look at minerals before moving on to look at how they influence rocks.

So let's get started by looking at what we mean by the term mineral.

I'd like to start by asking where you may have heard the word mineral before.

Now, you may have heard it referred to when talking about mineral water, or perhaps mining for minerals.

You may have even come across the word mineral when talking about nutrition.

But when we're talking about rocks, the term mineral refers to something completely different.

It's a pure substance, it's naturally occurring and it's usually formed by a geological process.

Now, minerals can exist as either elements or compounds, and we have some examples here.

Copper, for instance, would be an elemental mineral and we can tell it's an element because its chemical symbol is simply Cu, and I would be able to find that on the periodic table.

Another example of a mineral is quartz.

Now this is an example of a compound mineral, and we know it's a compound because its formula of SiO2 shows two different elements that have been chemically combined, making it a compound.

Let's stop here for a quick check.

Which statements below about minerals is or are correct? Well done if you said A, B, and D.

All three of these are correct about minerals.

They're pure substances, elements or compounds.

They are definitely not a mixture.

So well done if you've got at least one of those correct, and incredibly well done if you've got all three.

Fantastic start, guys, keep it up.

Now, a key feature about a mineral is that it has a crystalline or crystal-like structure.

And I have some examples here, and they may not match exactly, you might imagine a crystal looks like, but to a scientist, if they were to look at these structures a little bit more closely, they would all have what's described as a crystal-like structure.

Now, minerals also can be grouped according to their chemical composition.

So I have here four examples of minerals.

I have quartz, garnet, emerald and dumortierite.

Now if I look at their chemical composition a little bit more closely, I can see that all of them contain silicon and oxygen.

Now because of that, despite the fact that all four of these look very different from each other, they are all examples of the same mineral group, a silicate, and that's because they all contain those elements of silicon and oxygen bonded together.

Now, interestingly, even within a mineral group, the specific chemical composition of each mineral distinguishes it from the other minerals.

So again, if we look at these four examples, quartz, garnet, emeralds and dumortierites, and I look at those chemical compositions more closely, I can tell they're all in the same mineral group, those silicates because of the silicon and oxygen in their chemical composition.

But taking a closer look, I can see the other elements in those compositions are slightly different, and it's this that makes them individually different minerals.

Now those different chemical compositions, those very specific chemical compositions are really important because a mineral's chemical composition and its crystalline structure combine to give it its very distinctive physical properties.

And those physical properties are things like it's colour, its hardness, so how easy is it to scratch and it's lustre.

So what it looks like when it's reflecting light.

So we might use words like metallic or silky to describe how that particular mineral is reflecting light.

And this is all due to both its chemical composition and that crystalline structure combined, giving it those properties.

Let's stop here for another quick check.

True or false, only specific minerals have a crystalline structure? Well done if you said false.

But which of these statements best justifies that answer? Well done if you said A.

All minerals have a crystalline structure, it's one of the features that distinguishes a mineral.

So very well done if you managed to get those correct, guys.

Fantastic job.

Okay, let's move on to the first task of today's lesson.

What I'd like you to do is use words from the box to complete sentences below.

So you may wish to pause the video here and come back when you're ready to check your answers.

Let's see how you got on.

For sentence A it should read, "Minerals are pure substances, they can be elements or compounds." Now for that last sentence, you could have also had, "They can be compounds or elements," that would be equally correct.

For B, it should read, "All minerals have a crystal-like or crystalline structure and specific chemical composition." And C should say, "The structure and composition give each mineral its particular physical properties." So very well done if you managed to correctly use your keywords in the sentences to fill them in.

If you didn't, you may wish to pause the video here and correcting your mistakes, so that you have a nice summary about minerals that you can refer back to later on in your learning.

Very well done if you've got those correct.

Great job, guys.

For this next task, I would like you to consider these samples.

Now, all four of these samples contain a silicate mineral, but what are two other physical properties of the samples that might indicate they all contain a similar mineral? You may wish to discuss your ideas with the people nearest you.

So pause the video and come back when you're ready to check your work.

Okay, let's see how you got on.

Now, there are a few different physical properties you could have chosen, and we already gave you that they were different by their colour, so we needed to choose two other physical properties.

And I would've said something along the lines of how hard it is, and perhaps it's lustre, so how shiny it might be, or what it looks like when it's reflecting light.

So very well done if you managed to get either one or both of those correct, guys.

Fantastic work.

Now, the last part of this task looks a little bit more closely at lustre.

Now, we said earlier that a mineral's lustre describes how it reflects light.

What I'd like you to do here is to match each lustre description to the correct minerals.

You have four different minerals that are shown, and your mineral descriptions are metallic, glassy, dull and silky.

And again, you may wish to discuss your ideas with the people nearest you.

So definitely pause this video and come back when you're ready to check your answers.

Okay, let's see how you got on.

So for letter A, the galena, I would've described as being a metallic lustre.

For B, the gypsum would've been described as a silky lustre.

The limonite in letter C would've been described as dull, which means the quartz of letter D would've been described as glassy.

So very, very well done if you managed to get those correct, guys.

You are doing a fantastic job.

Keep it up.

Now that we're feeling a little more comfortable describing what a mineral is, let's look a little more closely at what a rock is.

Now, the word rock is actually often used as an adjective, for instance, rock band, or rock sweets, or even rock climbing.

But to scientists and geologists specifically, the word rock refers to a solid material that is a mixture of minerals or organic matter, and organic matter could be the remains of plants or animals.

So which statement below about rocks is correct? Well done if you said C, most rocks are mixtures.

The other three statements describe minerals.

So very well done if you got that correct.

That's a great start to this part of the lesson.

Keep it up.

Now, scientists can use this description of rocks to refer to a wide variety of materials, including rock that might be loose.

And what we mean by that is that its grains aren't sticking together strongly enough to be considered the solid rock that we might be more familiar with.

So when I'm talking about this type of rock where the grains aren't sticking together, I'm talking about things like sand, gravel, clay, those hard materials, those grains that if you were to pick it up into your hand, it would literally filter through your fingers.

That's still considered rock, even though it's not hardened together and stuck together.

However, these parts of rock could actually combine to make a stronger whole and form these rocks that we are more familiar with, like pumice, marble or shale.

Now, the minerals within a rock can all be the same type of mineral, like silicate minerals or sulphide minerals, or it's more common actually to find multiple types of minerals within a rock.

So for instance, granite contains minerals of feldspar, minerals of quartz and minerals of mica in it.

It's still a mixture, and it's a mixture of multiple different types of minerals.

Let's stop here for another quick check.

True or false, most rocks are composed of just one type of mineral? Well done if you said false, but which of these statements best justifies that answer? Well done if you said A, rocks are mixtures composed of different minerals.

Very, very well done if you got that correct, guys.

Let's move on now to the next task in today's lesson.

For this first part, I'd like you to use the words rock or mineral to fill in the gaps below.

Now, you may wish to talk over your ideas with the people nearest you.

So pause the video and come back when you're ready to check your answers.

Okay, let's see how you got on.

So the first paragraph should look like this.

A mineral is a solid that is found in nature.

It is a pure substance that has a crystalline structure.

Quartz is an example of a mineral.

A rock is made of one or more minerals that are combined in one place.

A rock may contain remains from plants and animals.

Limestone is a rock that is made of a mineral called calcium carbonate and small amounts of other materials.

Now, these two words are very easily confused, so if you did get any of these incorrect, it's really important that you pause the video and correct those mistakes, so that you have a clear summary of both of these words being used correctly that you can refer back to later on.

So very, very well done though if you've got those correct, guys, you're doing an amazing job.

Keep it up.

Now for this next part of the task, I'd like you to consider these six examples.

Now, there are rocks of many different colours, shapes, and sizes, and sometimes they can be really hard to tell if something is made of rock.

So what I'd like you guys to do is to classify these six different materials as being either made of rock, containing some rock, or has no rock in it at all.

So you may wish to discuss your ideas with the people nearest you.

So have that discussion whilst you've paused the video, and then come back when you're ready to check your answers.

Okay, let's see how you got on.

Now, I would've said that these are the materials that were made of rock, so the pebbles, the gravel, and the clay.

And I would've said that the soil contains some rock, but that the gold and the diamond has no rock in it at all.

And one of the reason I say that is because gold is an element that I can find on the periodic table, and therefore it is a mineral.

And diamond is another pure substance that is formed of just one element.

It's carbon.

And again, that would be considered a mineral.

So I am very impressed if you've managed to get those correct.

The diamond was a particularly difficult one to classify, but very, very well done if you managed to get that correct, guys.

Great, great job.

Now, in this last part of this task, I want you to think about rocks and crystals, 'cause it can be really difficult to distinguish between a rock and a crystal.

And some pupils are discussing what they think this sample might actually be.

Is it a rock, is it a crystal? So I'd like you to read the pupil's statements on the next slide and then answer the questions.

Now as I go through these student statements, I'd like you to consider, who do you think is correct about whether or not this sample is a rock or a mineral? And I'd like you to try to explain your choice.

So I'm looking for that because clause to support your decision.

Aisha reckons it's made of crystals, so it's a mineral, whereas Jacob thinks it's a rock made of one sort of mineral.

Sofia thinks the different crystals are all stuck together to make rock, whereas Sam reckons it's a rock because they can see a mixture of different materials.

And Lucas reckons it's a mineral because there's no grey or brown rock.

So who do you think is correct about whether this is a rock or a mineral and why? You may wish to pause the video to discuss your ideas with those around you and then come back to check your work.

Okay, that was quite a tricky task, but let's see how you got on.

I would've said that Sofia was on the right track because she's recognised that there are different crystals within this sample.

Also, Sam was also on the right track because Sam's recognised that rock is a mixture and not something that is a pure substance.

So very well done if you chose Sofia or Sam, and incredibly well done if you were able to include that because clause to support your choice.

Very, very well done.

What I'd like to look at next then is why are the other statements incorrect about whether or not this sample is a rock or a mineral? Again, now that we know who was correct, have a think, pause the video and come back when you're ready to check your answers about why these other statements might not be correct about this being a rock or mineral.

Now, Lucas thought that this particular sample was a mineral because there was no grey or brown rock in it.

But rocks are actually defined by more than simply colour, and not all rocks are simply grey or brown either.

So we need to be looking at more than simply colour to classify this sample as rock or mineral.

Now, Jacob thought that this was a rock made of one sort of mineral, but if that was true, then it should be classified as a mineral.

Rocks are mixtures made up of more than one mineral.

So what Jacob's done is he's confused his use of our keywords because if it's one sort of mineral, it's a mineral.

If it's a rock, it's a mixture of many minerals, okay? And now Aisha thought that it's made of crystals and so therefore it's a mineral.

But again, this is a little tricky thing here.

Rocks contain minerals and minerals are crystalline, which means that rocks can also contain crystals.

So I can see her thinking here, but it was a little bit unclear on whether or not it should be a rock or a mineral.

So just because it has crystals doesn't mean it's a mineral.

Rocks can also have crystals because they contain minerals.

So those were really, really tricky.

But very well done if you got anything along those lines to explain why these particular statements weren't helpful in helping us to classify the material as a rock or a mineral.

Very, very well done on an incredibly tricky task.

Now, we've gone through a little bit of confusing material today, so let's take a moment to summarise what we've learned.

Well, we've learned that a mineral is a pure substance, so is either an element or a compound, and that they have a crystalline or crystal-like structure, and that minerals are distinguished from one another by their crystal structure, their chemical composition, and those two features of a mineral, give them specific physical properties, things like its hardness and its lustre, or how it might reflect light that shines upon it.

And that rock by contrast is a mixture of minerals, rock fragments, or organic matter.

I hope you've had a good time learning with me today.

I certainly had a good time learning with you, and I hope to see you again soon.

Bye for now.