• 2 months ago
Transcript
00:00ROCKS AND MINERALS
00:04Our planet earth is almost entirely made up of rocks.
00:11Hills, mountains and valleys are made of rocks.
00:19Stones and pebbles are made of rocks.
00:25Even the garden soil and sand are made up of many tiny particles of rock.
00:33Rocks are found under the soil and at the bottom of rivers and seas.
00:42Now let us look at the different types of rocks.
00:47Some rocks are hard, some are soft while some are shiny.
00:55They are of different colours too.
00:59They may be grey, black, red and white in colour.
01:07If a rock is tightly pressed and heated for a few million years, it can turn into a new kind of rock.
01:18For example, sandstone becomes quartzite, shale becomes slate and limestone becomes marble.
01:31Now let us have a look at a few rocks and their different uses.
01:38Marble
01:41It is a hard rock.
01:44It is used in our homes for flooring.
01:48It is also used for making statues, buildings and furniture.
01:55It comes in different colours.
01:58Taj Mahal is made up of white marble.
02:03Granite
02:05It is a very hard rock.
02:08It shines and looks attractive when polished.
02:13Large slabs of granite are used for floors.
02:18It is also used for making kitchen and bathroom platforms.
02:24Sandstone
02:27It is also a hard rock but not as hard as marble or granite.
02:35It is used in construction.
02:38Our very own Red Port in Delhi is entirely made of red sandstone.
02:47Slate
02:49It is a soft grey rock.
02:54Some houses have roofs made of slate.
02:58Blackboards and slates used for writing are also made of slate.
03:05Chalk
03:08It is a soft rock.
03:10It is used by a teacher to write on the blackboard.
03:16Lastly, Charcoal
03:19It is also a soft rock.
03:23It is used as fuel in engines and for cooking in villages.
03:31Now, let us see what these rocks are made up of.
03:37All rocks are made up of minerals.
03:42Most rocks are made up of two or more minerals.
03:48Minerals
03:50Now, let us learn more about minerals.
03:54Minerals are not easily available.
03:58We need to extract them from the rocks before we can use them.
04:05We use minerals in our daily lives.
04:09Minerals come in different colours and shapes.
04:14Now, let us look at a few minerals, their properties and uses.
04:22Iron
04:25It is commonly found and hard.
04:29It is used to make tools and nails.
04:33Quartz
04:36It is commonly found and hard.
04:40It is in crystal form.
04:43It is found in different colours.
04:46Different gemstones are made from it.
04:50It is also used in watches.
04:54Talc
04:57It is the softest mineral and there are no crystals in it.
05:02It is used to make talcum powder.
05:06Silica
05:09It is hard and commonly found in nature as sand or quartz.
05:16It is used to make mirrors and glasses.
05:21Salt
05:24It is very important and a basic necessity.
05:29It adds taste to the food.
05:33Tungsten
05:36It is hard.
05:38It is used in light bulbs and tube lights.
05:43The glowing filament in them is tungsten.
05:48Clay or China clay
05:52It is soft.
05:54It is used to make pottery and decorative plates.
06:00Graphite
06:03It is soft and grey in colour.
06:07The lead of pencils is made of graphite.
06:12Lastly, gemstones
06:15Gemstones are very hard minerals.
06:20They are also called precious and semi-precious stones.
06:27These stones are very expensive.
06:31Some gemstones have a very peculiar colour.
06:37These stones are cut into different shapes and sizes and are polished before using in jewellery.
06:47Now we know that rocks and minerals help us in our day to day life.
06:54Hence, it is important to use the mineral resources wisely.