Some rocks are very hard. What is the hardest rock? A. diamond B. quartz C. obsidian D. gneiss 相关知识点: 试题来源: 解析 A。解析:diamond(钻石)是最硬的岩石。quartz(石英)、obsidian(黑曜石)、gneiss(片麻岩)都没有钻石硬。本题考查词汇比较。
What metamorphic rock does obsidian turn into? What type of rock is formed exclusively from contact metamorphism? What are non-clastic sedimentary rocks? What tools does igneous petrology use? Which foliated rock is the lowest grade metamorphic rock?
What type of igneous rock is basalt? What type of rock is corundum? What type of rock is quartzite? What type of rock is magnetite? What type of igneous rock is obsidian? What is basalt rock? What kind of rock is soapstone? What is feldspar used for? What is extrusive rock? What mi...
obsidian flows. The absence of crystal growth is explained by the inhibition of atomic diffusion by this high-viscous lava. Obsidian is difficult, fragile and amorphous and therefore has strong corners of fractures. The instruments for slicing and piercing were previously used and were used as ...
What Color is Obsidian? As mentioned, obsidian is produced during the rapid cooling of volcanic lava. It is a formed rock with very sharp edges, mostly used for cutting and piercing tools, and for scalpel blades for surgical purposes.
Obsidian, a type of rock, is primarily composed of mineraloids, lacking a crystalline structure. 2 Minerals Naturally occurring, inorganic substances with a specific chemical structure. Quartz and feldspar are two common minerals found in the Earth's crust. 2 Rocks Aggregates or combinations of on...
These rocks include:andesite, basalt, dacite, obsidian, pumice, rhyolite, scoria, and tuff. What is another name for igneous rocks? Igneous rocks are also known asmagmatic rocks. Igneous rocks are divided into two types: plutonic and volcanic rock. ...
In this case, use the rock as your sharpener. You could also take a rock and break off some of the edges and then use another rock and some water like a wet stone and sharpen. In an ideal situation, obsidian stone would be used for its infamous sharpness.77.___An...
glass-like structure. This rock was a common material for arrowheads due to its ability to chip easily and sharpness. When chipped, obsidian has both the appearance and the slicing ability of broken glass. It is also a very hard rock, so it is unlikely to shatter on impact with its targe...
Basalt is a dark-colored, fine-grained,igneous rockcomposed mainly of plagioclase and pyroxene minerals. It most commonly forms as an extrusive rock, such as a lava flow, but can also form in small intrusive bodies, such as an igneous dike or a thin sill. It has a composition similar to...