History of Diamond Mining in Africa

Diamonds are one of the hardest minerals known to man. It is made up of 99.5% pure carbon and the remaining .05% elements determines the diamonds colour and shape. It is believed that the first diamond mines were discovered in a little country called India 500 BC. For two thousand years India was the largest producing diamond countries producing some of
the worlds most are diamonds found before the get cut and polished for sale. The big rough diamonds sometimes are cut into two diamonds such as the Cullinan one and the Cullnian two . They were cut out of a diamond that weighed 3106 carats.

Once a diamond is mined it is taken to a artisan who determines the most important components of the diamond. When you are in the market to purchase a diamond, you need to consider the 4 C’s. CARAT This refers to the diamond’s size by weight. Each Carat represents 100 points. CUT This part of the diamond is influenced by man. The cut of the diamond does not refer to the shape of the cut diamond but rather the craftsmanship applied in cutting the facets of the stone. A well cut diamond is one that reflects the most light. CLARITY When diamonds are born shall we say, along their journey they may have embedded in them natural elements called inclusions. An artisan will examine the stone very closely. They will then decide which is the best way to cut the diamond to achieve optimum brilliance by eliminating the inclusion or by reducing it. COLOUR This is one part of the diamond that is not determined by man. The closer the diamond is to colorless the more pure and valuable the diamond is. The color grades are D, E and F. F is considered a colorless diamond that is rare.

Diamonds钻石Diamonds are rare,beautiful,and also quite useful.They are the hardest substance found in nature.That means a diamond can cut any other surface.And only another diamond can make a slight cut in a diamond.钻石既珍贵稀缺，又美丽晶莹，也用途很广。

钻石是自然界里最坚硬的物质。

这就意味着钻石能划破任何物体的表面。

只有另一块钻石才能在一块钻石上留下轻微的划痕。

Diamonds are made from carbon.Carbon is found in all living things,both plant and animal. Much of the carbon in the earth comes from things that once lived.钻石（金刚石）由纯碳所组成。

在一切生物中，包括动物和植物，都含有碳。

地球上的绝大部分碳都是来自从前的生物。

Scientists know that the combination of extreme heat and pressure changes carbon into diamonds.Such heat and pressure exist only in the hot,liquid mass of molten rock deep inside the earth.It is thought that millions of years ago this liquid mass pushed upward through cracks in the earth's crust.As the liquid cooled,the carbon charged into diamond crystals.科学家们都知道，只有在极高的高温和高压这两个条件结合起来的情况下，才能把碳转化成金刚石（钻石）。

高二英语完形填空试题(有答案和解析)一、高中英语完形填空1．阅读下面短文，从短文后所给的四个选项（A、B、C和D）中，选出可以填入空白处的最佳选项。

Once there was a farmer in Africa named Hafiz who was happy and content.One day a(n) 1 man came to him and told him about the glory of diamonds and the 2 that goes along with them. The wise man said, "If you had a diamond the size of your thumb, you could have your own city. If you had a diamond the size of your fist, you could probably own your own 3 ." With that said, he went away. That night the farmer couldn't 4 . He was unhappy and he was 5 .The next morning he sold off his farm, took care of his family and went 6 diamonds. He looked all over Africa and couldn't find any. He looked all through Europe and couldn't find any. When he got to Spain, he was emotionally, 7 and financially broke. He got so 8 thathe threw himself into Barcelona River and committed suicide.Back home, the person who had 9 his farm was watering the camels at a 10 that ran through the farm. Across the stream, the rays of the morning sun hit a stone and made it 11 like a rainbow. He picked up the stone and 12 it in the living room.That afternoon the wise man came and saw the stone sparkling. He asked, "Is Hafiz 13 ?" The new owner said, " No, why do you ask?" The wise man said, "Because that is a diamond. I recognize one 14 I see one." The man said, "No, that's just a stone I 15 from the stream. Come, I'll show you. There are many more." They went and picked some samples and sent them for 16 . Sure enough, the stones were diamonds. They found that the farm was indeed 17 with diamonds.When our 18 is right, we realize that we are all walking on acres and acres of diamonds. Opportunity is always under our feet. We don't have to go anywhere. All we need to do is 19 it. When people don't know how to recognize opportunity, they complain of 20 when it knocks. The same opportunity never knocks twice. The next one may be better or worse, but it is never the same one.1. A. young B. wise C. old D. poor2. A. history B. meaning C. power D. legend3. A. country B. house C. factory D. farm4. A. eat B. wake C. stand D. sleep5. A. tired B. discontent C. confused D. sick6. A. in search of B. in need of C. by name of D. by way of7. A. similarly B. gradually C. actually D. physically8. A. puzzled B. discouraged C. impatient D. exhausted9. A. robbed B. seized C. paid D. bought10. A. pool B. river C. stream D. lake11. A. smooth B. sparkle C. rise D. flow12. A. hid B. deserted C. put D. stored13. A. out B. back C. away D. dead14. A. unless B. until C. if D. when15. A. discovered B. stole C. searched D. made16. A. display B. operation C. analysis D. revision17. A. provided B. covered C. supplied D. equipped18. A. summary B. spirit C. goal D. attitude19. A. ignore B. avoid C. recognize D. respect20. A. noise B. appearance C. waste D. trouble【答案】（1）B；（2）C；（3）A；（4）D；（5）B；（6）A；（7）D；（8）B；（9）D；（10）C；（11）B；（12）C；（13）B；（14）D；（15）A；（16）C；（17）B；（18）D；（19）C；（20）A；【解析】【分析】本文是一篇记叙文，一位农民为了追求财富而放弃农场，最后情绪、身体和经济都破产了，自杀了。

The End of the Rainbow 彩虹的尽头作者：By V. M. Hillyer ——V. M. 希利尔来源：《时代英语·高一》2020年第06期V. M.希利尔（1875—1931），美国著名的儿童教育家、科普作家，创建了卡尔弗特教育体系。

他为孩子们编写了一套趣味盎然的历史、地理、艺术读物，即《写给孩子看的世界历史》《写给孩子看的世界地理》《写给孩子看的艺术史》。

本文选自《写给孩子看的世界地理》。

Gold！It used to be said there was a pot of gold at the end of the rainbow， though no one has ever found it. Yet men have left their business and their families and homes and gone to the ends of the earth in search of gold and to find a short cut to riches， for gold is used for money all over the world， though small coins are not made of it because they would have to be too small and would easily be lost.The largest gold mines in the world are in South Africa， and more than half of the gold in the world comes from gold mines near a city there called Johannesburg.金子！传说在彩虹的尽头有一罐金子。

可是没有人真正走到过彩虹的尽头，找到这罐金子。