Looking through the encyclopedia and seeing all kinds of beautiful pictures, the child said that he was going to the mountain to pick up stones, but also to pick up gems, all kinds of colors.
The four gemstones mentioned in the book
There's actually a name called "Half Jewel."
Therefore, whether you can pick up the desired stone becomes a question that can be considered.
There is no time to climb the mountain in the short term, and it is not clear whether there are any gems on the mountain, so let's first learn about the stones on the earth.
Encyclopedic classification of rocks
According to the book, tens of thousands of natural minerals have formed about 500 different kinds of stones on Earth through different combinations (mixtures of various minerals). There are three main categories:
Igneous, metamorphic and sedimentary rocks.
This article mainly looks at igneous rocks.
igneous
The formation of igneous rocks is mainly the formation of crystals when molten magma or lava cools and solidifies, and the crystals are formed very tightly and gaplessly, so most of the igneous rocks are very hard. It is often said that granite is igneous rock.
Encyclopedia content
During the formation of igneous rocks, the color of the rocks that are eventually formed is different due to different magmatic compositions and different minerals. The lightest colored granite in the image above was formed after basalt and diorite.
Deep diagenetic
Magma deep underground cools and solidifies to form deep diagenetic rocks. Because they are separated by surrounding rocks, the cooling process of magma can last millions of years, and the minerals in the lava have a considerable amount of time to separate and crystallize, which allows the crystals to grow very large.
Fast-cooling magma, such as the mineral crystals of volcanic lava, cannot grow very large.
volcanic rock
The rocks that erupt from the volcano cool down very quickly, so the crystals in the solidified lava are small and often invisible to the naked eye, so the volcanic rock has its own name. Rhyolites, for example, are ejective rocks corresponding to granite that may not have a pronounced crystal structure and often crack to form unique shapes when thick lava rheology cools and contracts, especially when basalt condenses and shrinks into hexagonal columns.
This image comes from the network, "Giant's Causeway", a set of basalt lava flows
The Giant's Causeway in Northern Ireland is a set of basalt lava flows formed by volcanic eruptions about 55 million years ago, with about 40,000 basalt columns.
Igene Invading Rock
Despite the high temperatures, high pressures allow most of the mantle lava beneath the Earth's crust to remain solid. However, once the pressure is released, or once the melting point of the lava is lowered (something such as water is added), the rock will melt into magma, not as dense as the solid mantle rock. Magma rises through the mantle, may slowly cool and solidify underground, or erupt through volcanoes to become liquid lava.
Some of the most spectacular rock types on Earth are formed when lava is squeezed upward into the brittle crust. When they cool, they crystallize to form huge rock foundations and deep diagenetic masses, volcanic necks, wall-like veins, and horizontally spread out rock beds. As the relatively soft surrounding rocks are eroded, these intrusive rocks are exposed and stand out over the landscape. This is the case for the following seven landscapes.
Large african rock veins
The Great African Rock Veins in the Encyclopedia
Big Karoo, Africa
Tower Sugar Mountain
Mount Kinabalu
Hipproc Peak
Bodmin Gonuma
Devil's Tower
The above is the relevant content of igneous rock, for the time being, there are so many, to be added later.
There are two other types: metamorphic rocks and sedimentary rocks, the contents of which will be sorted out next time.
metamorphic rock
sedimentary rock