Admin Table of Contents
- 1 What are the important factor needed to form a rock?
- 2 Which factor is most important in determining which minerals will form in a rock?
- 3 What three factors are necessary to form gneiss rock from a sedimentary rock?
- 4 What is the most expensive rock?
- 5 Where is gneiss most commonly found?
- 6 How does rock mass affect tensile strength of rock?
- 7 How are rocks formed and what are they made of?
- 8 Which is the best description of a nonfriable rock?
What are the important factor needed to form a rock?
The process depends on temperature, pressure, time, and changes in environmental conditions in the Earth’s crust and at its surface. The rock cycle illustrated in Figure 1 reflects the basic relationships among igneous, metamorphic, and sedimentary rocks.
Which factor is most important in determining which minerals will form in a rock?
The most important factor in determining which minerals will form in a rock is the composition of the rock. Some minerals will only form when certain chemicals are in a rock.
What makes a rock harder?
The chemical bonds that hold atoms together in these minerals are stronger in some than in others, and the atoms themselves determine which bonds are stronger than others. Stronger bonds make for stronger minerals and, thus, harder rocks.
What three factors are necessary to form gneiss rock from a sedimentary rock?
The mineralogy of a particular gneiss is a result of the complex interaction of original rock composition, pressure and temperature of metamorphism, and the addition or loss of components. A gneiss is produced by intense metamorphism, at high temperature and pressure.
What is the most expensive rock?
Jadeite – $3 Million Per Carat Jadeite is the most expensive mineral, or rock, in the world at this time. Price per carat for this costly gem is three million dollars a carat! Jadeite’s beauty and rarity are what makes this rock so pricey.
How hard is a normal rock?
If you can barely see the grain, the rock is very hard. It is more difficult to assess the hardness of rocks than the hardness of minerals. If you are using a pocket knife, the average hardness of this tool is approximately 6.0 to 6.5 and if you are using a metal saw, it should be around 6.5 to 7.0 on Mohs scale.
Where is gneiss most commonly found?
Gneisses result from the metamorphism of many igneous or sedimentary rocks, and are the most common types of rocks found in Precambrian regions. Gneiss is found in New England, the Piedmont, the Adirondacks, and the Rocky Mts. Some gneisses are used as facing stone on buildings.
How does rock mass affect tensile strength of rock?
In general, rock mass strength depends on the strength of intact rock and the strength of rock discontinuities. In general, compared to intact rock, a rock mass has reduced tensile strength (almost zero), and reduced shear strength especi ally along discontinuity planes.
How to calculate the strength of a rock?
According to equation (17) the strength ratio Fc/Ft (or Co/To) depends on the value of m only.For limestone m=5.4 and Co/To=5.6; for granite m=29.2 and Co/To=29.2; for sandstone m=14.3and Co/To=14.3. The Hoek and Brown criterion for intact rock can also be expressed in terms of normal andshear stresses as follows (18)
How are rocks formed and what are they made of?
“Rocks are hard mass of mineral matter comprising one or more rock forming minerals”. Rocks are formed from the molten material known as magma. The study of rocks is called Petrology (in Greek, petra means rock, logos means science). Petrology deals with the description of rocks.
Which is the best description of a nonfriable rock?
Slightly friable or nonfriable rocks consisting mainly of soft minerals, as carbonates, Hard. Nonfriable rocks consisting almost entirely of minerals with hardnesses of 4, 5, or 6 on the Mohs scale, and quartz-rich rocks with strength of 6 or 7.