How to distinguish stones from minerals?

To find out the answer to the question of how a stone differs from a mineral, you need to take into account the chemical structure and use of these substances. In principle, stones can be called minerals and vice versa, there will be no gross mistake in this. But there are still several significant differences by which these elements are distinguished and classified.

Principles of Distinction

• The existence of minerals and rocks. This classification is basic in mineralogy. Its essence lies in the fact that minerals are substances that have a homogeneous structure, but rocks or simply stones are heterogeneous in composition.
• Minerals are used in jewelry, and stones are more often found in industries and construction.
• From an esoteric point of view, minerals have magical properties, but stones do not.
• The cost of stones sometimes differs thousands of times from the price of minerals. Minerals are always more expensive, there are fewer of them in nature, since there are always fewer pure substances than materials with impurities. They look more beautiful, but there are more benefits from ordinary stones or rocks. Rocks make it possible to extract heat and are used in many energy sectors.
• Natural origin. Minerals are products of nature that are found directly in the soil. Therefore, shellby, rhinestones and other stones made in the laboratory cannot be called minerals, but they can be called stones. Organic substances, for example, amber and jet, do not fit into the category.

Ideally, minerals are truly homogeneous; most often the crystal contains impurities, which are called defects or inclusions, and the price of the product drops because of this. If a mineral is called a stone, then it is better to choose the adjective “precious”, “semi-precious” or “ornamental”.

Classification of stones

There is no classification of stones and minerals as such. Jewelers divide stones according to one characteristics, geologists and mineralogists – according to others, sellers – according to the value of the goods. The first attempts to organize stones arose from Kluge and Gurich, professors of mineralogy.

Bauer brought clarity to this matter in 1986. Thus, he divided all gems into precious, ornamental and stones of organic origin. Moreover, rock stones were not included in this classification. In turn, the classes were divided into orders. But now it is customary to use the classification of V. Ya. Kievlenko, which distinguishes the following groups:

1) Jewelry stones. Usually representatives of this category are the most expensive and beautiful:

• i order: diamond, emerald, sapphire, ruby;
• II order: alexandrite, tadyite, sapphire, except for the blue shade, black opal;
• III order: demantoid, spinel, noble white and fire opal, aquamarine, topaz, rosolite, moonstone, red tourmaline;
• IV order: varieties of tourmaline, artificial zircon, individual representatives of beryl, turquoise, chrysolite, amethyst, chrysoprase, pyrope, almandine, citrine.

2) Jewelry and ornamental stones.

• i order: rauchtopaz, bloodstone hematite, rock crystal;
• II order: agate, colored chalcedony, cahonite, amazonite, rhodonite, heliotrope, rose quartz, iridescent obsidian, common opal; Labrador; white porous, spar.

3) Ornamental stones or those from which you can make not only jewelry, but also interior items. These include: jasper, ganite, onyx, colored marble, obsidian, fluorite.

Most minerals are formed in the earth in the form of crystals, that is, they crystallize and acquire a regular arrangement of atoms, ions, and molecules. Often crystals have a strict shape and edges. And their lattice, that is, the internal structure, determines such properties as shape, hardness, density and type of fracture.

But rocks are aggregates that consist of several parts fused together. Their characteristics and structure depend on the conditions of formation, including temperature and the depth of the stone. All stones are classified into groups such as:

• Igneous. The stones lie deep in the ground (more than 100 kilometers) and come to the surface along with magma during a volcanic eruption.
• Sedimentary. Rocks that form on the surface of the earth under the influence of weather conditions.
• Metamorphic. Stones that are obtained as a result of changes in the original rocks due to tectonic movements of the earth or the effects of temperature.

By the way, this classification may include some minerals, for example, tourmaline, topaz, quartz. There is also a classification based on characteristics such as the physical and chemical composition of the stone. In this case, the scientist distinguishes:

• nuggets (diamonds);
• sulfides;
• halides;
• oxides;
• nitrates, carbonates;
• sulfates and phosphates;
• borates;
• silicates.

Each group fits about 10-15 stones. If at least one element from the periodic table predominates in a stone, then a group of specimens will be named after it, for example, if the composition contains arsene, then the stones will be called arsenates. In total, more than 4 thousand types of stones, including minerals, have been discovered, so the classifications are very voluminous and difficult to remember.

All methods of arranging stones are of little interest to jewelers, since their main task is to determine the value and process the specimen, and not its chemical composition and name. It is cost that plays a significant role in determining whether it is a stone or a mineral. If it is a stone, then craftsmen and gemologists decide how precious it is.

Cost of minerals and stones

Sometimes, to find out and calculate the cost, it is enough to understand whether the stone is genuine or not. But in most cases with transparent crystals and diamonds, the issue is resolved using the table and the “4C” assessment:

• Clarity. This factor indicates impurities in jewelry. Sometimes they can be hidden by cutting. They are formed during the growth of a mineral under natural conditions. Inclusions in the structure are allowed to be of a certain location and size. If it is a semi-precious stone, then less attention is paid to inclusions. And if a specimen cannot be processed due to a large number of impurities, then it is no different from an ordinary stone from the ground.
• Color. The range of shades of minerals is varied. There are specimens that have several shades and they are still called minerals, not stones. There are options that change color depending on the lighting.
• Cut. Jewelry is given a shape that emphasizes its brilliance and other advantages.
• Weight (in carats). Products are weighed and valued in carats. One carat is equal to 0,02 grams.

Of course, no one evaluates ordinary stones and rocks according to these criteria, since they are not isolated, but are valued as a whole. Stones are transported in hundreds of tons, regardless of shape and size. And deposits of minerals and ordinary stones also have different localizations. The industries for the extraction of specimens do not overlap; the technology itself and the volumes of specimen extraction may differ.

Stones and minerals, although they belong to the gifts of the Earth, still differ in content from each other. It is enough that stones are a broader concept that includes minerals. But each type of stone is used because it is needed by humanity for different reasons.

What can you find on the earth and right in it?

The outer hard shell of our planet, the lithosphere, consists of rocks. Most of them were formed during natural processes – the settling of shells to the depths of ancient reservoirs, the spread of small pieces of mountains through glaciers, winds and currents. These rocks are called sedimentary, and they consist, respectively, of minerals and soft or hard organic substances.

An example of a sedimentary rock is limestone, which is composed of the remains of marine animals. They are found in limestone and fossils – teeth and bones, paw and body prints, traces of the vital activity of organisms, etc. Fossils are formed when organic substances from a dead creature are replaced by minerals deep in the earth over thousands of years. Then these remains appear on the surface again as a result of the movement of the crust and the destruction of the upper rocks.

In addition to sedimentary rocks, there are also igneous rocks, which appeared due to the activity of volcanoes and the solidification of their magma or lava (for example, volcanic glass, basalt and granite), and metamorphic rocks – this is when the original rock changes due to various physical and chemical reactions. The latter includes marble, from which, thanks to its radiance and variety of colors, monuments, furniture and decorative items are made.

A piece of rock that can be found in different parts of the Earth is a stone, i.e. a solid fossil. By the way, rocks exist not only on Earth, but also on the surface of other planets, satellites, asteroids and meteorites.

What is the mineral that makes up most rocks? This is a natural chemical compound that usually takes the form of a crystalline solid. Minerals have a uniform composition and certain properties, i.e. different density, texture, fragility, shine, etc. We can say that most minerals are crystals, but not every crystal is a mineral. The fact is that minerals are always of natural origin, but a crystal can be created artificially.

There are about five thousand minerals on Earth, some of which are very expensive. The latter are called precious stones. A mineral is considered precious if it is rare, durable and beautiful. Jewelry is made from such stones, and collectors (and sometimes criminals) hunt for them. Nowadays, diamonds (which, after cutting, turn into diamonds), rubies, sapphires, emeralds, and alexandrites are considered precious. Less rare minerals are called semi-precious stones. These are, for example, topaz, amethyst, garnet, opal, etc. Ancient people made the first tools from minerals, then they began to serve as the basis for jewelry and currency, and even later – as materials for construction and industry.

How to support a child’s hobby: home experiments

If your child is seriously interested in minerals, it’s time to start a collection (either pure minerals or stones with various mineral inclusions). First, research your region and find out what breeds are most common in your area. Samples of minerals can be found in souvenir shops at museums, artisans and even factories. If you wish, you can order them online. And don’t forget to bring pebbles from family trips to the sea and mountains! You can also purchase a special kit for growing crystals or try making them yourself with just salt and water. This way, the child will be able to clearly distinguish crystals from minerals.

To expand your child’s knowledge, buy a specialized atlas that helps identify rocks by appearance. When the collection begins to gather, you can move on to home experiments and research.

The collection is fascinating to look at under a microscope or with a magnifying glass. Invite your child to compare minerals or rocks that have an identical composition, but are not at all similar to each other in appearance and properties. For example, you can study diamond (i.e., cut diamond) and graphite (pencil lead), which are composed of the same carbon. In the same way, you can compare limestone (in the form of a piece of chalk) and marble, consisting of calcite.

You can also have your child weigh rocks to make sure that their size and weight are not always related. Another option is to determine the hardness of samples by the depth of the mark that can be left by a nail.

Some rocks can be identified by running a stone across a piece of paper and looking at the thickness and color of the stripe left behind. The mineral can also be rubbed on a hard surface, for example, on a piece of kitchen tile. The streak you get may not even be the same color as the mineral itself.

If desired, some minerals can be attracted with a magnet and melted using a candle or lighter. Moreover, it makes sense to even smell some samples: inclusions such as sulfur can cause the appearance of a rotten smell.

You can also break the found stone with a hammer and see what inclusions of minerals are visible on the scrap. With your child, analyze how the stone split: the number of fragments, sharp edges, etc. Finally, it is interesting to observe rocks by dipping them into different liquid media, for example, vinegar.

It is convenient to record the results of all these experiments in a geological journal. You can also paste pictures of stones there or draw them from life with the whole family.

Older children can be enrolled in the geological section, if there is one in your city. Under the guidance of a specialist, the children study minerals and organize field trips to practice, as well as to exhibitions in neighboring cities. For serious observations, you can purchase a schoolchild a Mohs mineralogical scale or a special pencil to determine the hardness of a stone, as well as a black field magnifying glass, with which you can easily see inclusions even in transparent minerals.

Interesting facts about stones and minerals for children

Many minerals received original Latin, Greek or Oriental names due to their shades. For example, red hematite is named after blood. Sometimes minerals are named because of their different properties: for example, pyrite received its name from the word “fire” due to its ability to create sparks when struck. Plants may also appear in the names: malachite is similar in color to a mallow leaf, and pomegranate is similar to grains from the fruit of a pomegranate tree.

For some people, minerals have a symbolic and esoteric meaning; with their help they even try to treat diseases and enter into communication with the other world. However, we should not forget that among the stones there are also those that are dangerous to humans. For example, charoite can be highly radioactive, and cinnabar contains a lot of mercury and its harmful effect is similar to a broken thermometer.

Precious minerals are still mined by hand. For example, to extract a one-carat emerald, you need to process about 20 tons of earth. But sometimes it happens that animals help people. For example, in America there is a place where an expensive type of pomegranate is mined. by ants. They simply throw the mineral to the surface when they build their homes.

The hardest mineral on our planet is diamond. It forms deep in the earth, and the bond between its carbon atoms is very strong. As a result, for example, using a diamond drill it is possible to drill through any rock. The largest diamond in the world, the Star of Africa, weighs about 600 grams. There are also planets in our Universe that are almost entirely made of diamond.

The world of stones is amazing: it can tell not only how our planet works now, but also what it was like hundreds of thousands of years ago. So don’t rush to scold your child if he once again digs in the ground or picks something up from the road. Thanks to children’s interest in rocks, you can instill a love of nature and history, and also make the whole family a lot of cool crafts from stones – from paintings to jewelry.