第十二课

12 understanding rocks12认识岩石

1. Rocks can be seen almost everywhere. Do you know what kinds of rocks there are?1、岩石几乎随处可见，你知道岩石有哪些种类吗？

Material package材料包

Cotton, self-adhesive label, etc.棉花、自粘性标签等。

Task card任务卡

Collect different types of rock.搜集不同种类的岩石。

Activity process活动过程

What are the characteristics of the rocks observed and collected?观察搜集到的岩石，它们有哪些特点？

To observe the characteristics of rock, it is necessary to observe on the new section of rock.观察岩石的特征，需要在岩石的新断面上观察。

Pay attention to safety when using hammer and knife.使用锤子、小刀时要注意安全。

index card for files资料卡

1. Different rocks have different hardness. After knocking open the rock, use fingernail and knife to mark on the new section

Test the hardness of rock. The rocks with scratches after fingernail scratching are soft; There's a scratch on the knife The rock is very hard; The hardness of the rock which has not been scratched with a knife is very high.1、不同岩石的硬度不同。敲开岩石后，用手指甲、小刀在新断面上划可以测试岩石的硬度。用手指甲划后留有划痕的岩石较软；用小刀划后留有划痕的岩石很硬；用小刀划后也没有留下划痕的岩石硬度非常大。

1、Observe the rock specimen to understand the rock characteristics.观察岩石标本，了解岩石特征。

There are black spots in the granite.花岗岩中有黑色的斑点。

I observed that........我观察到。。。。。。。。

This is marble.这是大理岩。

index card for files资料卡

marble大理岩

Generally white, it contains different impurities, presents different colors and patterns, soft.一般呈白色，其内部含有不同杂质，呈现出不同颜色和花纹，较软。

Sandstone砂岩

Most of them are black, maroon or greyish green, with dark luster and very hard.常见的多呈黑色、褐红色或灰绿色，光泽较暗，很硬。

Granite花岗岩

Variegated, mostly light flesh red, light gray or gray white, etc., very hard花斑状，多为浅肉红色、浅灰色或灰白色等，很硬。

Development activities拓展活动

Classify the collected rocks and make rock samples.给采集来的岩石分类，制作岩石标本。

Label the rocks.给岩石贴上标签。