Gemstones and Crystals

Gemstones and Crystals

Planet Earth

Before we begin our research into the World of gemstones and crystals let’s take a look at planet Earth and her structure. Mother Earth is a massive ball of rock 7,927 miles in diameter and weighs about 6.6 sextillion tons. A sextillion, for those who don’t know, is the unit number 1 followed by 21 zeros. So, if we were to write down the weight of the Earth on paper it would appear like this – 6,600,000,000,000,000,000,000 tons.

The Earth is composed of a dense inner core which is primarily a solid ball of iron and nickel. Its outer core is made up of iron, nickel, and a convection of liquid metals such as gold, platinum, and uranium. These metals can also be found on the surface of the Earth in solid form.

The Earth’s continents are islands of granite rock floating on dense, dark rocks underlying ocean basins that may go down as deep as 600 miles. Minerals of economic value are derived from the lighter granite rocks and rocks sourced from the lighter layer of granite. Mountains form when some darker rocks come to the surface of the Earth and are visible.

Minerals

Minerals are inorganic chemical compounds or elements that occur naturally in the Earth’s crust. Some minerals have a fixed chemical structure and some are a string of related compounds where one metallic element may partly or wholly replace another. For example, jadeite and spodumene are two minerals that are very similar in chemical characteristics and much alike in some of their physical properties. However, both minerals do vary greatly in colour and some other physical properties.

Elements

Elements are a class of substance that cannot be broken down into simpler substances by chemical processes. They are the building blocks of all materials, including rocks and minerals, and created by only one type of atom. All atoms of an element have the same number of protons, however, can differ in the number of electrons and neutrons they possess. Elements are defined by the number of protons they contain in the nuclei of their atoms. There are 94 naturally occurring elements on Planet Earth and 24 synthetics, a total of 118 elements.

periodic table of elements

Source: E. Generalic, https://www.periodni.com/images.html

Geology 

Geology is the scientific study of the Earth’s structures and materials. Its history and the processes that have caused it to change over time. Divisions within the science of Geology include, Mineralogy which is the study of minerals, Petrology the study of rocks, and Crystallography the experimental science and analysis of the seven crystal structures. 

Crystals

Crystals are stunning both in natural beauty and proportion. And there appears to be some sort of mathematical formula to how they form in such amazing symmetry. Perfect crystals however are very rare and extremely valuable and the majority of the crystals on our planet are characterised with inclusions, blemishes, distortions or some kind of interruption during their development. And some crystals form in clusters or as twins.

 7 Crystal Structures

There are seven crystal systems in mineral identification:

Cubic (Isometric) System – Crystals comprising three axes of equal length at right angles to one another, as in a cube. Examples are Diamond, Garnet, Halite, and Pyrite.

  1. Hexagonal System – Crystals have two axes of equal length and one axes different in length. All three axes are at right angles to one another. Examples are Cassiterite, Rutile, and Zircon.