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All the videos we've created for Mining A Sustainable Future have full transcripts. You can read through them at your will, or click the video titles to go straight to that transcript.

Alt text is available for all of the images used for Mining A Sustainable Future. We have split the images into sections for ease of access. All images are listed below, alternatively you can click on a section heading to go straight to those images.

Introductory Video

Cornish Lithium Video

Jadarite

Understanding the Chemistry of Rocks

Using X-Rays to Understand Rocks

Rocks under the microscope

Rocks under the scanning electron microscope

Website: Home Page (excluding storymap)

Storymap: The incredible diversity of metals and minerals on our planet

Storymap: Exploration

Storymap: Mining

Storymap: Reducing Environmental Impact

Storymap: Mine rehabilitation

Harnessing natural phenomenon - Metal Munching Bacteria

Transcripts

Transcripts heading

Introductory Video

In recent years parliaments around the world signed into action a number of plans aimed at countering climate change and creating a cleaner, greener future for our society. Whether it be moving to electric vehicles, or creating energy using new, green technology, on the surface, it looks as though these plans will go a long way into tackling climate change, however when you dig deeper, challenges arise.

Although green technologies might seem like a departure from mining, in truth these technologies require an enormous amount of metal. We need to stop and think about where these metals come from. So how do we mine a sustainable future?

At iCRAG and the Natural History Museum, we research Critical Metals. Critical metals include Lithium, Cobalt, Nickel, Copper, Zinc, the Platinum Group Elements and the Rare Earth Elements. These metals are critical because they are vital to society. They are used in things like solar panels, wind turbines, rechargeable batteries in our cars or EVs, electric vehicles. And because of this, demand for these critical metals is growing dramatically. There is a saying in geology: If it can’t be grown, it has to be mined.

We aspire towards a circular economy in which we recycle and reuse every material and don’t generate any waste. A lot of current scientific research focuses on this effort. However, at the moment recycling and reusing are not able to meet the growing demand for the metals that we need for the energy and technology revolution. Mining continues to be needed to supplement this excess demand of metal.

When we think of a mine, we often recall images of 19th century coal mines with workers covered with soot or unsightly holes in the ground. Although mining has a chequered past, recent developments are allowing it to become much more environmentally friendly and less invasive. New ways of processing are using nature’s own solutions to breaking down minerals and extracting metals.

Our researchers are using non-traditional ways to look for the metals we need. For instance, we look at things like historic mine wastes, other industrial wastes to see if they contain metals. And we’re using high technology laboratory analyses to accomplish this.

Certain metals, such as lithium, will play a key role in the energy transition towards a zero-carbon future. One of our aims to reduce the impact of mining in our environment is finding domestic sources and stop relying on imported supplies of metals. In the “Lithium for UK project” we teamed up with Cornish Lithium and Wardell Armstrong International and have succeeded to produce the first known lithium carbonate from UK hard rock sources, which is essential for the UK automotive and battery industries.

Mining is going to remain a key part of our economy until it transitions into one that’s fully circular, but in the meantime, we can work together to make mining even more sustainable.

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Cornish Lithium Video

CL Vid

Cornish Lithium is exploring for lithium down in the southwest of England. The lithium is contained within the granite rock which underlies the whole county and there’s also the potential to produce lithium from geothermal waters which circulate naturally at depth.

But how do we find this lithium? How do we explore for it and ultimately extract it?

Cornwall has an amazing mining heritage. People have been mining tin and copper here for thousands of years and it's been a really serious industry for many hundreds of years. This means that we’ve got lots of data about the subsurface from this historic mining industry. So, as an exploration geologist, your first job is to gather as much information about the subsurface as you possibly can.

This information could be in the form of old maps or plans and sections that have been drawn through the old mines, it could be geophysical data which gives you information about the properties of the rocks underneath the surface, or it could be satellite imagery or imagery from drones that you’ve flown.

We use high tech technology to combine data from all of these different data sets, historic and modern, in 3D digital space. Building these 3D digital models of the subsurface then let’s us work out where is the geology that we’re interested in, what rocks lie at what position underneath our feet. We use these 3D digital models to design where we want to put boreholes. Drilling is the ultimate test of seeing if what you have modelled is underneath of surface, is actually there. We've designed drilling programmes to allow us to take samples of lithium enriched granite from depth and work out what the possible resource size might be. We’ve also designed drilling programmes to allow us to sample geothermal waters from depth.

Through drilling, we found there actually is potential for producing lithium from Cornwall, there's the potential to produce lithium from the hard rock site and there’s also the potential to produce lithium from geothermal waters.

So, the next stage in our exploration programme now is going to be to do more drilling to actually understand this potential size of that resource.

In parallel, we’re also doing work to see how you can extract that lithium, whether it’s from the hard rock source or from the geothermal waters. This involves taking lots of samples of the geothermal waters or the hard rock and putting it through lots of different tests to see what is the most efficient way to extract the lithium.

We're looking at using extraction technologies that are as environmentally responsible as they possibly can be. We want to extract the lithium in the most low carbon manner possible. Because it's not just the grade of the lithium and the size of the resource that are important in mineral exploration, but you also need to consider the environmental and social impacts of you actually extracting that resource. So, a lot of the work that we are doing in Cornish Lithium is to better understand exactly what these environmental and social impacts might be if we extract lithium down here in Cornwall.

The work we've done so far suggests that if we embrace these new technologies to help us explore more efficiently and extract the lithium more efficiently, then we can do this, it is possible to do this in an environmentally responsible low carbon manner. And we really think that building a new lithium extraction industry in the UK, meaning that we don't have to import it from other countries around the world, could be really beneficial to Cornwall and the whole UK.

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Jadarite

So, one of my jobs here at the Museum is understanding the diversity of the Mineral Kingdom. Part of that means researching and finding entirely new minerals; those are basically materials that are new to science and new to nature. And about 10 years ago we had a really interesting discovery. We were approached by mining company who found the material that they did not know what it was, and we used our amazing collection here as a reference point to try and compare and contrast the material they had with what was already in the collection. And we were able to show that it was something completely new. So, it was a mineral that had not been found before and so when we get interested like that, we start doing a lot of advanced chemical tests and working out where all the atoms go into making this material up. And it turned out that this material was really interesting for two reasons. So firstly, the chemistry that we found out was lithium boron silicate of some variety and that happened to be almost identical to a completely made-up chemical formula that was used in “Superman Returns” for the composition of kryptonite and so there was quite a lot of fun, we did a lot of press stuff about that in a sense, have scientists really actually found kryptonite? And of course, we had not, it was a pure chance that a year before our discovery someone have made up chemistry that was almost exactly identical as the material that we found, and there was a lot of fun, about, well, maybe we should call it “kryptonite” but that would be inaccurate because it actually doesn’t actually contain any of the element of krypton, which is a real thing. And so instead we named it after where it is from and it is actually called “jadarite”, which is after a Jadar basin in Serbia, where the material was found. I have got here an interesting sample, which is actually the very first one that was found, and this is where all of our original data and chemistry came from. This is the most important sample of this that we have, it is something called “a type specimen” and we look after this like really really carefully. The second reason why this was such an important discovery was that the mineral contains element lithium. Lithium is really important for our everyday life at the moment. It is essential material that goes into the batteries that make up our mobile phones, that make up the tablets and a lot of other electrical devices. And so we need more of it and the discovery of this new material gives us a new option and new route in terms of being able to extract that material. And it just goes to show how important it is for us, as geologists and mineralogists, to keep exploring and to keep using our collections to find completely new things that might change the world that we live in.

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Understanding the Chemistry of Rocks

Rock Chem

Scientists are interested in the chemical make-up of rocks for several reasons. This information can tell us how the Earth has changed through geological time, how volcanoes erupt and how past climates have changed.

Knowledge of the chemistry of rocks is also important in the mining industry, to optimise and target their processes effectively, and in the processing of the rocks to make sure the elements are in the appropriate amounts to be turned into the products that they are mined for.

To analyse the elemental composition of rocks, we need to break the rock down, because the elements are packaged into various minerals, like the different colours you can see in this rock.

We do this in two ways: by melting the rock - a process known as fusion - and dissolving the rock in acid, which creates solutions that we can then analyse.

Lithium is a metal which is important in batteries and therefore crucial to developing a green, sustainable society in the future.

Lithium is difficult to analyse because we use a lithium-based flux for the fusion process, but we can analyse it from the acid digestion.

To fuse a rock, we heat a known quantity with a flux at around 1,000-1,200 degrees until it completely melts and then quench it into a glass bead.

The bead is then dissolved in a weak acid until the solution is clear.

To dissolve the rock in acid, we weigh a known amount and dissolve it in a mixture of acids.

We run the solution in one of two instruments: one that uses light (or electromagnetic radiation), and one that uses the mass of the element to determine how much there is in the sample.

Both instruments use inductively coupled plasma, which is like a very high-energy flame.

Plasma is known as the fourth state of matter, and the plasmas we have in our instruments are at a similar temperature to the surface of the Sun.

This instrument uses optical emission, where an element is given extra energy from the plasma, which temporarily moves some of the electrons in the atom. And when these electrons go back to their original orbitals, they emit some light in the ultra-violet and visible wavelengths.

Here you can see the element yttrium changing the colour of the plasma as it emits light in the visible range.

The light that each atom emits is like a fingerprint, and when we run the unknown samples with known standards, we can determine with reasonable precision the concentration or amount of the element in our unknown sample.

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XRay rocks

Using X-Rays to Understand Rocks

So, X-ray diffraction is an important tool for studying crystalline materials.

We use this technique to determine the crystal structure of minerals - for instance, of these beautiful lepidolite crystals.

With X-ray diffraction it is possible to visualise how atoms are arranged in a structure and how atoms are linked together in three dimensions.

The atomic arrangements of nearly all known crystalline materials have been determined using this technique.

At NHM, we use X-ray diffraction to study crystal structures of minerals that are new to science, and minerals that have potential technological importance in the future - such as minerals that contain critical elements.

In an X-ray machine, we expose a small crystal to a fine beam of X-rays, and we collect a diffraction pattern at a specific detector.

Such a diffraction pattern is unique for each substance. It is the fingerprint of a crystalline material.

So we can also use X-ray diffraction also for identification of substances.

Identification is achieved by comparing a diffraction pattern with a pattern from a reference database.

There are huge databases available with crystal structures of thousands of materials that we can use for comparison.

This is an example of a diffraction pattern of a white powder extracted from a lithium-bearing rock in the UK, in Cornwall.

The diffraction peaks match very well with a substance called lithium carbonate.

Lithium carbonate is a starting material - a good starting material - for production of lithium-ion batteries. With our measurements, we confirmed that the complex, sophisticated lithium extraction process was a success.

The material is the first known production of nearly battery-grade lithium carbonate from a UK source.

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Rocks under the microscope

Rocks microscope

After we successfully located a mineral deposit and started mining it, we end up with a piece of ore very much like this one, which, along with about 20,000 other ore specimens, forms part of the Natural History Museum's collections.

Like most other rocks, an ore is made up of different minerals.

So some of these minerals will contain elements we are interested in, like copper for example, or gold.

Others just have no economic value, like pyrite which is also called fool's gold.

And then some minerals will even contain elements that can be hazardous, like arsenic for example.

So, before we start extracting metals, we have to separate these minerals first.

With a reflected light microscope such as this one here, we can have a look at a polished section of the ore and identify the minerals in there - but also the relationship between the minerals, their grain sizes and their textures.

This is not only important to figure out how the deposit has formed - all these factors will ultimately also determine which technique we have to apply to separate these minerals.

So, in the example we are looking at at the moment, we're looking at a tiny speck of gold (the shiny one in the middle), along with some dark grey zinc mineral, yellow copper mineral, a pale yellow iron mineral (which is pyrite or fool's gold) and a white lead mineral.

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Rocks under the scanning electron microscope

Rocks under the SEM

This is a scanning electron microscope, which we use to identify different minerals.

And we can see very, very small, down to a thousandth of a millimetre.

It works by firing a beam of electrons at the samples and then measuring the energy of the X-rays that are generated.

Minerals are made up of different elements in certain ratios, and so these X-rays that we generate tell us the amount of each element present, and so we can work out what that mineral is.

This is an automated system, so it takes millions of analysis points. And we can identify minerals that we wouldn't otherwise find if we were controlling the beam manually, like we used to.

We also, because we got so much data, we get a lot of information about the abundance and size and shape of the minerals that are present.

Lithium minerals are very challenging to analyse, because, in this technique, we can't really analyse elements that are lighter than oxygen - which, unfortunately, includes lithium itself.

However, all is not lost and we can use our knowledge to identify certain minerals from the other elements present that we think might contain lithium.

And we can also see the mass that's missing in the analysis.

So, for example, a tiny amount of rubidium is often a good indication that there's lithium present in the minerals.

So we can use this technique to identify those minerals and their size and shape and abundance, and then take them onto a slower, more advanced technique - such as laser ablation mass spectrometry - where we can actually measure the lithium and see exactly how much is there.

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Harnessing natural phenomenon - Metal Munching Bacteria

Metal Munching Bacteria

Hello everybody I'm Dr Ana Santos and I'm a research scientist at Bangor University in North Wales. Here at Bangor our research focus is on microbes that live in very extreme environments called extremophiles, particularly the acid loving ones.

These microbes are present in many different environments including freezing cold polar regions, but also very hot volcanic areas, highly acidic lakes and streams, and also deep down in the ocean. But they are not just surviving in these places in these extreme conditions, the really like it in there!

Many years ago, researchers found out that these microbes can be used in several industrial applications, including mining and this is what we call biomining: the use of microorganisms to extract valuable metals from ores and wastes.

Before we apply any of the biomining techniques, first we need to understand the basic needs of the microbes - what do they like to eat? Some of them like marmite in a small amounts, do they prefer to live with or without air? Alone, or as part of a community? What's their optimum growth temperature and pH?

To answer some of these questions we need to run tests in the lab, but we can also get very important information just by taking a peek at their DNA.

The key to successfully cultivate them in the lab is to mimic the conditions in which they would be living in nature. Once we have that sorted we can put them to work!

Here at Bangor, we mainly use bacteria in our processes. Right now in this bioreactor bacteria are growing and multiplying. You can't see it with the naked eye, but believe me, there are thousands of millions of them in there.

To extract valuable metals from ores and mine wastes, first we grow them in these bioreactors then we add the metal rich material to the reactor and let them do the work! In this case here we're extracting metals from alimonite which is considered waste in laterite processing.

After a few days we separate the liquid from the solids and we end up with these beautiful colourful solutions, and each metal has its own colour. We analyse the liquid phase to know how much of each metal has been extracted. We can use different techniques to separate and concentrate a specific metal from a solution.

After that, it's pretty much ready to go into your smartphone!

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Alt Text

Website: Home Page (excluding storymap)

Five windturbines situated in a field of yellow flowers. In front of the windturbines, in the field of yellow flowers, there are two rows of solar panels. The sky is blue and cloudless.

Image copyright Wix

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The mineral sphalerite as seen under a microscope. The mineral is different shades of brown. It looks as though the mineral is composed of different circles surrounded by a glassy matrix. The mineral has a cracked appearance.

Image copyright Aileen Doran and reproduced under a CC license.

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Storymap: The incredible diversity of metals and minerals on our planet

The mineral Assurite which appears as a bright blue and green growth on a rock speckled with red, grey and white.