Minerals have a variety of physical and chemicals properties that can be evaluated using simple tests. The under mentioned checking method can tell us about mineral with simple laboratory tools and equipment. However, in some cases some tests can be dangerous for minerals and gemstones.
- Mohs Hardness Scale
- Crystal Shape
- Specific Gravity
Hardness in any mineral tells us about resistance of a mineral. How much a mineral has an ability to resist against environment or changes? Minerals are formed by different durability level and characteristics. There are various levels of checking the hardness of a mineral. One can check the hardness of mineral with simple scratching with an hard tool on the surface of the mineral.
Mohs Hardness Scale
Three is a list of hardness of common minerals. During checking of hardness test, it may destroy the mineral so care should be taken. The hardness of minerals and Mohs Hardness Scale are studied and examined used in laboratories .
A pure Iron and magnetite (Fe3O4) are rocks which have magnetic effects. There are also some meteorites which has iron rich having magnetic effects. There are many minerals having richness of iron which are half magnetic and have magnetic susceptibility which can be measured as well.
We can judge the mineral or a gem through its colour. Colour can be observed by necked eye easily. But we cannot trust on colour regarding identification. A single mineral can be observed in various colours such as tourmaline, spinels, topaz etc
Luster is another thing which interprets the mineral. A luster tells us how the light is reflected from a mineral’s surface. Luster can tell us if the mineral reflects metallic, shiny, g=glassy, silky, early or non metallic from surface. .
Through streak we can identify the mineral through scratching its surface specially in soft minerals. After scratching, there remains a colour on the surface of the mineral. The streak of mineral can be different from the actual coloour of mineral also. This is very useful for the minerals having less than 7 hardness. However streak test can also destroy a mineral. Care should be maintained while doing this test.
— there are some minerals which have colour effects changes under different lights. For example if you throw a backlight in fluorite, or zinc mineral or Petroleum Quartz, they will glow in different colours. However mostly rocks and minerals cannot be fluorescent.
Fluorescent minerals from Baluchistan Petroleum Quartz
There are various types of crystals shapes which is formed by mineral’ atoms. Shape results from the pattern formed by the atoms of a mineral when it is forming. Example is various shapes of quartz crystals.
Specific Gravity means that what is the ratio of mineral mass in equivalent with equal volume water mass.
This is can tell weakness of crystal structure. For example when the miner picks mineral from mine in breakage form, it can tell the type of fracture. Whether the fracture is irregular or appears to be like a broken glass.