Home Geography for Primary Grades · Lesson XLII · Unit 9: Things found in the earth
42. More about things found in the earth: stone, brick and glass
Goal: Your child names the common building stones (granite, sandstone, limestone, marble, slate), knows a quarry, and knows that brick, mortar and glass are made from clay, lime and sand.
You'll need
- A few rocks or stone things to look at: a piece of granite (a countertop sample or gravel), sandstone, a piece of chalk, a slate or roof tile, marble (a tile or coaster)
- A brick if you have one
- A little white vinegar and an eyedropper
- A magnifying glass
- A geography notebook (any notebook kept just for these lessons) and a pencil
What's in the book
Building stones come from quarries. Granite is hard and enduring and used for steps, paving and curbs; sandstone (including brownstone) is made of grains of sand and crumbles more easily; limestone is burned in a lime-kiln to make lime; marble is beautiful when polished; chalk is a soft limestone; slate splits into thin plates for writing and roofs. Brick is made of clay, mortar of lime, and glass of sand. Visit mines and quarries if possible.
The lesson, step by step
A quarry
Read the opening and look at the pictures of the granite and marble quarries.
The place from which stones are taken for building is called a quarry.
Granite and sandstone
Look at granite and sandstone with the magnifying glass. Granite shows speckles of different crystals; sandstone shows tiny grains of sand. Rub each with a coin: which crumbles? (sandstone)
Ask the book's questions: What does "enduring" mean? What does "crumble" mean?
Limestone, chalk and marble
Drip a little vinegar on chalk, a piece of limestone or marble, or a seashell. Look for tiny bubbles.
SayLimestone, chalk and marble are all made of the same thing as seashells, and vinegar makes them fizz. Granite does not fizz.
Ask: Is chalk harder or softer than other stone? Could you build a house of it?
Slate
Look at a slate or slate tile. Ask: What is slate used for? (writing slates, roofs, floors) Why is it good for these? (it splits into thin, flat, smooth plates)
Brick, mortar and glass
Read the last part. Ask: Is brick found in the earth? (No, but it is made of clay, which is.) What is mortar made of? (lime, from limestone) What is glass made from? (sand)
Stones in town
Take a walk and look for stone: granite curbs and steps, brick walls, slate roofs, marble on old buildings or in a cemetery. Ask: Which is the best building stone, and why?
Afterwards
Start a small rock collection, as the book's preface suggests, in an egg carton with each stone labeled with where it was found.
Tip
Visiting a quarry: look from a public overlook only. Quarry edges and quarry ponds are dangerous. The book's lime-kiln is for watching only, too: quicklime burns skin.
Answers to the book's problems
A quarry is a place from which stone for building is taken. Granite is used for steps, paving and curbs, and sometimes for buildings, because it is easily shaped, strong and enduring. "Enduring" means lasting a long time; "crumble" means to break into small bits. Sandstone (brownstone is one kind) crumbles more easily than granite. Lime is made by burning limestone in a lime-kiln. Marble is used for statues, table tops, mantelpieces, steps and buildings because it is beautiful when polished and lasts long. The book says marble and granite are the most beautiful and enduring building stones. Chalk is a soft limestone, too soft for building. Slate is used for writing slates and for roofs because it splits into thin, smooth, firm plates. Bricks are made of clay and are used for walls, houses, chimneys and paths; the man who builds with them is a bricklayer or mason. Mortar is made chiefly of lime. Glass is made from sand.
Worked out for this site from the scan. If a number in your copy differs, trust the book.