Several rocks are practical in our daily life. Rocks contain minerals that help us in life. Rocks can help in developing new technology. A man can use the rocks and minerals for building material, manufacturing cars, used for roads, and many others—several types of rock help in developing the new technology. Schist and Gneiss are the two different types of metamorphic rocks with minerals and hardness.
Schist vs Gneiss
The main difference between Schist and Gneiss is that Schist is a metamorphic rock obtained from mudstone or shale. In contrast, Gneiss is one of the types of metamorphic rock formed from igneous or sedimentary rocks. Schist and Gneiss rocks are formed by following different methods.
Schist is a metamorphic rock sculptured from mudstone or shale. Schist is a medium-grade rock that contains layers. Schist rocks have medium and large-sized, consist sheet-like grains, and flat with preferred orientation. These rocks had made with a high range of minerals like muscovite, talc, biotite, graphite, chlorite, sericite. Feldspar and quartz are extremely less generous in the Schist rocks. The Sub-type of Schist rock had Mica Schist.
Gneiss is one of the types of metamorphic rocks. Gneiss had formed from igneous and sedimentary rocks. Gneiss forms at high temperatures and high pressures acting on the metamorphic rocks in the process. Gneiss had derived into two types. Orthogneiss is the type of gneiss rock formed from igneous rocks and, Paragneiss is formed from sedimentary rocks. Feldspar and Quartz had high in these gneiss rocks.
Comparison Table Between Schist and Gneiss
| Parameters of Comparison | Schist | Gneiss |
| Meaning | Schist is a medium-grade metamorphic rock. | Gneiss is an ordinary and distributed metamorphic rock. |
| Formation | Schist had shaped from mudstone or shale. | Gneiss had shaped from sedimentary rocks or igneous rock at high temperature and high pressure. |
| Sub-types | Mica Schist is the sub-type of the Schist metamorphic rock. | Orthogneiss and Paragneiss are the sub-types of Gneiss rock. |
| Hardness | The hardness of the Schist had 4-5 on the Moh’s scale. | The hardness of the Gneiss rock is 7. |
| Minerals | Muscovites, talc, biotite, graphite, chlorite and sericite. Feldspar and quartz are small in amount and are less generous. | Gneiss contains quartz, potassium feldspar and sodium feldspar. Also, a small number of muscovite, biotite and hornblende are present in the Gneiss rocks. |
What is Schist?
Schist is a medium-grade metamorphic rock formed at high temperatures and high pressures. Schist rocks had formed from the mudstone or shale rock at high pressure and temperature. The Schist metamorphic rocks are flat and medium in size. Schist rocks contained sheet-like grains with preferred orientations. The solidity of the Schist rocks is 4-5 as per the Moh’s Scale. Schists can divide easily. Some of the types of igneous rocks can form the Schist rocks.
Mica Schist is a sub-type of Schist rocks. Minerals like Muscovites, talc, biotite, graphite, chlorite, and sericite are present in the Schist. Muscovite, talc, biotite, graphite, chlorite, and sericite. 4-5 is the relative solidity indicate by the Moh’s scale against other rocks and minerals. Some names used for Schist rock had three words, similarly granite, graphite and, schist rocks. Granitic, Shale, and Volcanic rocks are the parent rocks of Schists. Schists had used for tarmac, garden decoration, and occasionally for sculptures. Schist is not a very strong rock but, sometimes it is used as building materials.
What is Gneiss?
Gneiss is one of the metamorphic rocks obtained from igneous rock and sedimentary rock at high temperature and high pressure. Gneiss is an ordinary and widely dispensed rock. It had a foliated structure. Gneiss had a solidity up to 7 as per the Moh’s scale and, the compressive strength of the gneiss rock is 125.00 N/mm sq. The Gneiss rock had crushed and powdered. And the colour of the powder is a streak.
Orthogneiss is the sub-type rock formed from igneous where Paragneiss had formed from sedimentary rock. Gneiss consists of a small number of minerals like Muscovites, biotite, and hornblende and a high range of potassium feldspar, sodium feldspar, and quartz. Granitic, Volcanic, and Shales are the parent rocks of Gneiss. Gneiss is used as an ornamental stone for ornaments, flooring, facing stones on buildings, gravestones. The gneiss rock breaks uniform in size when hammered. Gneiss is similar to gabbro and granite and distinguishable from Schist rock and phyllite.
Main Differences Between Schist and Gneiss
- Schist is a metamorphic rock formed from mudstone or shale rock where Gneiss rock had obtained from igneous or sedimentary rocks.
- Schist is a medium-grade metamorphic stone, where gneiss rock had ordinary and widely dispensed stone.
- Mica Schist is a sub-type of Schist rock. In Contrast, Orthogneiss and Paragneiss are the sub-types of the Gneiss rock.
- The Small amount of Feldspar and quartz had present in Schist rock. But Potassium feldspar and sodium feldspar had high in Gneiss.
- The relative solidity of the Schist rock is 4-5 on the Moh’s scale. On the other hand, the firmness of the gneiss rock is up to 7 on the Moh’s scale.
Conclusion
Schist is a medium-grade metamorphic rock formed at high temperatures and high pressures. Schist rocks had formed from the mudstone or shale at high pressure and temperature. Mica Schist is a sub-type of Schist rocks. Minerals like Muscovites, talc, biotite, graphite, chlorite, and sericite are present in the schist rock. Muscovite, talc, biotite, graphite, chlorite, and sericite. 4-5 is the relative hardness indicate by the Moh’s scale against other rocks and minerals.
Gneiss is one of the metamorphic rocks obtained from igneous rock and sedimentary rock at high temperature and high pressure. Gneiss is ordinary and widely dispensed rock. It is in a foliated structure. Gneiss is used as an ornamental stone for ornaments, flooring, facing stones on buildings, gravestones. Gneiss breaks even in size when hammered. Gneiss is similar to gabbro and granite and distinguishable from Schist rock and phyllite.
References
- https://www.sciencedirect.com/science/article/pii/S0378778814005040
- https://pubs.er.usgs.gov/publication/pp1220