Deep beneath the geysers and hot springs of Yellowstone Caldera lies a magma chamber produced by a hot spot in the earth’s mantle. As the magma moves towards the Earth’s surface, it crystallizes to form young, hot igneous rocks. The heat from these rocks drives groundwater towards the surface. As the water cools, ions precipitate out as mineral crystals, including quartz crystals from silicon and oxygen, feldspar from potassium, aluminum, silicon, and oxygen, galena from lead and sulfur.
黃石火山口的間歇泉和溫泉深處 有一個由地幔中的熱點 所產生的岩漿室。 隨著岩漿移向地球表面, 結晶成為新生的熱火成岩。 這些岩石的熱量將地下水推向地表。 隨著水的冷卻,離子 以礦物晶體的形式沉澱出來, 包括矽和氧形成的石英晶體, 鉀、鋁、矽和氧形成的長石, 鉛和硫形成的方鉛礦。
Many of these crystals have signature shapes— take this cascade of pointed quartz, or this pile of galena cubes. But what causes them to grow into these shapes again and again?
許多水晶具有標誌性的形狀—— 像是這種並列的尖頭石英 或成堆的方鉛礦立方體。 為什麼它們一次又一次地 長成這些形狀呢?
Part of the answer lies in their atoms. Every crystal’s atoms are arranged in a highly organized, repeating pattern. This pattern is the defining feature of a crystal, and isn’t restricted to minerals— sand, ice, sugar, chocolate, ceramics, metals, DNA, and even some liquids have crystalline structures.
部分的答案在於它們的原子。 每個晶體的原子都以 高度有序的重複模式排列。 這種圖案是水晶的定義特徵, 而且並不局限於礦物質—— 沙子、冰、糖、巧克力、 陶瓷、金屬、DNA, 甚至連一些液體都具有晶體結構。
Each crystalline material’s atomic arrangement falls into one of six different families: cubic, tetragonal, orthorhombic, monoclinic, triclinic, and hexagonal. Given the appropriate conditions, crystals will grow into geometric shapes that reflect the arrangement of their atoms. Take galena, which has a cubic structure composed of lead and sulfur atoms. The relatively large lead atoms are arranged in a three-dimensional grid 90 degrees from one another, while the relatively small sulfur atoms fit neatly between them. As the crystal grows, locations like these attract sulfur atoms, while lead will tend to bond to these places. Eventually, they will complete the grid of bonded atoms. This means the 90 degree grid pattern of galena’s crystalline structure is reflected in the visible shape of the crystal.
每種晶體材料的原子排列 分屬六個不同的系列: 立方晶系、四方晶系、正交晶系、 單斜晶系、三斜晶系和六角晶系。 在適當的條件下, 晶體的生成 反映其原子排列的幾何形狀。 以方鉛礦為例,它具有 由鉛和硫原子組成的立方結構。 相對較大的鉛原子 排列為彼此成 90 度的立體格子, 而相對較小的硫原子 整齊地排列在鉛原子間。 隨著晶體的增長, 這些位置會吸引硫原子, 鉛則傾向於在這些地方結合。 它們最終完成鍵合原子的格子。 這意味著方鉛礦晶體結構的 90 度立體格子圖案 反映在可見的晶體形狀中。
Quartz, meanwhile, has a hexagonal crystalline structure. This means that on one plane its atoms are arranged in hexagons. In three dimensions, these hexagons are composed of many interlocking pyramids made up of one silicon atom and four oxygen atoms. So the signature shape of a quartz crystal is a six-sided column with pointed tips.
與此同時,石英具有六方晶體結構。 這意味著它的原子 在平面上排列成六邊形。 這些立體空間裡的六邊形是由許多 「一個矽原子和四個氧原子」 形成的互鎖金字塔所組成。 所以石英晶體的標誌形狀 是帶有尖角的六面柱。
Depending on environmental conditions, most crystals have the potential to form multiple geometric shapes. For example, diamonds, which form deep in the Earth’s mantle, have a cubic crystalline structure and can grow into either cubes or octahedrons. Which shape a particular diamond grows into depends on the conditions where it grows, including pressure, temperature, and chemical environment. While we can’t directly observe growth conditions in the mantle, laboratory experiments have shown some evidence that diamonds tend to grow into cubes at lower temperatures and octahedrons at higher temperatures. Trace amounts of water, silicon, germanium, or magnesium might also influence a diamond’s shape. And diamonds never naturally grow into the shapes found in jewelry— those diamonds have been cut to showcase sparkle and clarity.
根據環境的條件, 多數晶體能形成不止一種幾何形狀。 例如,在地幔深處形成的鑽石 具有立方晶體結構, 可以長成立方體或八面體。 鑽石的形狀取決於其生長的條件, 包括壓力、溫度和化學環境。 雖然我們無法直接觀察 地幔中的生長條件, 實驗室的實驗已經證明 鑽石傾向於在較低溫度下 生長為立方體, 而在較高溫度下則生成八面體。 微量的水、矽、鍺或鎂 也可能影響鑽石的形狀。 鑽石永遠不會自然地長成 珠寶中的形狀—— 那些鑽石經過切割 以展現閃耀和清晰度。 環境條件也影響是否會形成晶體。
Environmental conditions can also influence whether crystals form at all. Glass is made of melted quartz sand, but it isn’t crystalline. That’s because glass cools relatively quickly, and the atoms do not have time to arrange themselves into the ordered structure of a quartz crystal. Instead, the random arrangement of the atoms in the melted glass is locked in upon cooling.
玻璃由熔化的石英砂製成, 但玻璃不是結晶。 這是因為玻璃相對較快地冷卻, 而原子沒有時間 將自己排列成石英晶體的有序結構, 相反地,熔化玻璃中隨機排列的原子 是在冷卻時被鎖定。 許多晶體不會形成幾何形狀,
Many crystals don’t form geometric shapes because they grow in extremely close quarters with other crystals. Rocks like granite are full of crystals, but none have recognizable shapes. As magma cools and solidifies, many minerals within it crystallize at the same time and quickly run out of space. And certain crystals, like turquoise, don’t grow into any discernible geometric shape in most environmental conditions, even given adequate space.
因為它們與其他晶體 生長在非常接近的區域。 像花崗岩一樣的岩石充滿了水晶, 但不具有可識別的形狀。 隨著岩漿的冷卻和凝固, 其中的許多礦物質 同時結晶和迅速耗盡空間。 某些水晶,如綠松石, 在大多數環境條件下 不會長成任何可辨別的幾何形狀, 即使空間足夠。 每個水晶的原子結構 都具有獨特的屬性,
Every crystal’s atomic structure has unique properties, and while these properties may not have any bearing on human emotional needs, they do have powerful applications in materials science and medicine.
雖然這些屬性可能 與人類的情感需求無關, 但它們確實在材料科學和醫學上 具有強大的應用功能。