What is the difference between obsidian and granite

Igneous Rocks -. Basaltic Trachyandesite. Compare Rocks. Obsidian vs Granite. From Italian granito, which means grained rock, from grano grain, and from Latin granum. Curling, Gemstone, Laboratory bench tops, Tombstones, Used in aquariums. When the lava is released from volcano, it undergoes a very rapid cooling which freezes the mechanisms of crystallization. The result is a volcanic glass with a uniform smooth texture.

Granite is an intrusive igneous rock which is very hard, crystalline and is visibly homogeneous in texture and forms by melting of continental rocks. Banded iron for.. Compare Igneous Rocks » More. Obsidian vs Scoria. Obsidian vs Andesite. Though some rocks look identical, they have certain characteristics which distinguish them from others. Characteristics of rocks include texture, appearance, color, fracture, streak, hardness etc.

Granite vs Obsidian characteristics assist us to distinguish and recognize rocks. Also you can check about Properties of Granite and Properties of Obsidian. Learn more about Granite vs Obsidian in the next section. The interior uses of Granite include Countertops, Decorative aggregates, Entryways, Floor tiles, Flooring, Homes, Hotels, Interior decoration, Kitchens and Stair treads whereas the interior uses of Obsidian include Decorative aggregates and Interior decoration.

Due to some exceptional properties of Granite and Obsidian, they have various applications in construction industry. The uses of Granite in construction industry include As dimension stone and that of Obsidian include Arrowheads, Cutting tool, Knives, Scrapers, Spear points. Here you can know more about Granite and Obsidian. The life cycle of a rock consists of formation of rock, composition of rock and transformation of rock. The composition of Granite and Obsidian consists of mineral content and compound content.

You can also check out the list of all Igneous Rocks. When we have to compare Granite vs Obsidian, the texture, color and appearance plays an important role in determining the type of rock. Consider the effect of impurities on the obsidian color For examples, iron and magnesium may make obsidian dark green. Hematite or limonite add a red or brown color to the obsidian. A lot of microscopic rock and mineral particles usually cause the jet black color most closely associated with obsidian.

It can cause the obsidian to have a gold or silver shine if the bubbles were spread almost flat. Obsidian has a strong conchoidal fracture and luster. It means that the top of the fracture is curving smoothly like a seashell. Obsidian appears to be black. Minute inclusions and tiny crystals in the glass create it hue. Due to the near absence of mineral crystals in the glass, this smooth, curved form of fracture surface occurs.

Conchoidal fracture surface intersections may be sharper than a knife. Obsidian, igneous rock that occurs as a natural glass produced by the rapid refreshment of viscous volcanic lava. Obsidian is extremely silica-rich around 65 to 80 percent , low in water, and has a rhyolite-like chemical composition. Obsidian has a luster of glass and is somewhat stronger than window glass.

Thursday, November 11, For example granite will have interlocking minerals and sandstone will have a gritty, sandy feel. Young children need to experience these characteristics before they can internalize the name of a rock.

Just knowing a name of a rock is not enough. In this lab, students will use their observational skills to classify rocks. Rather than using a formal classification, the emphasis is on students developing their own criteria for rock classification.

Most children recognize obsidian as the rock that many Indians used to make arrowheads. The Indians chose obsidian for the same reasons that a geologist can recognize it. It is very hard, but more importantly it breaks into sharp edges that easily cut through many materials.

Note that broken obsidian looks like broken glass. Obsidian occurs in almost any color, depending on what trace elements are present in it. Black and brown obsidian are most common. Obsidian is an amorphous solid; that, it is a solid rock composed of silicon dioxide, but this material lacks crystalline structures.

It is one of very few exceptions to the rule that rocks are made of minerals. The obsidian that is in your kit comes from volcanoes near Clear Lake, California. Obsidian is formed when lava is cooled very quickly; it freezes before crystals can form. Have your students try to determine which part of a lava flow will cool quickly enough to form obsidian answer - the outer surface or "skin" of the flow.

This characteristic makes pumice extremely lightweight; it even floats in water you may wish to show this to your students. It is commonly light gray to blackish-gray in color. It is easily broken and has sharp edges. Like obsidian, pumice is volcanic glass; it thus looks glassy especially with a magnifying glass and lacks visible minerals. Pumice forms during eruptions of magma containing large quantities of gasses, such as water vapor, sulfur dioxide, and carbon dioxide.

The gas "froths" the magma as it erupts, forming bubbles.