Metallography

Introduction

The science of alchemy is believed to have originated in classical antiquity and dates back as far as 6000BC. The practice of alchemy was used to produce medicines, create new alloys, purify materials, and even to transform base metals into gold. In its early stages, alchemy was used as a tool to explore the mysteries of nature. Over time, it evolved into a philosophical system which incorporated the spiritual, mental and physical realms.

Alchemical Science

Alchemy is based on the theory that all matter is composed of four basic elements: water, earth, fire and air. Each element is said to have its own properties and an internal energy known as a “spirit”. This “spirit” is believed to be the source of all material things and it is believed that if one could manipulate the energies of the four elements, then one could change any substance from one form to another.

Alchemists experimented with combinations of the elements to create new materials, such as the “Philosopher’s Stone” or elixir of life. The Philosopher’s Stone was believed to be a substance that could turn any ordinary metal into gold. In medieval times, alchemists sought immortality through the transmutation of lead into gold and they studied alchemical processes in order to gain a better understanding of nature.

Aims and Purposes of Alchemists

The aims and purposes of alchemists were twofold. First, alchemists sought to discover the secrets of nature and the hidden forces that govern it. Second, they used this knowledge to create substances which could be used to improve the quality of life of humans. Examples of these substances were medicines, cosmetics, dyes, paints, explosives and alloys.

Alchemical Symbols

The alchemists used symbols to represent their material substances and to communicate the physical and spiritual influences at work in each experiment. These symbols were later divided into two categories: spiritual and material. Symbols are the key to understanding the philosophy of alchemy. Spiritual symbols represent the spiritual forces at work in each experiment while material symbols refer to the physical components. For example, a triangle is commonly used as a symbol for fire, while a circle might represent an element.

Alchemical Processes

Alchemists also used processes to transform materials and create new substances. Alchemical processes are divided into two main steps: the “putrefaction” process, which breaks down the material into its basic elements, and the “coagulation” process, which combines the elements into something new. For example, the transmutation of lead into gold, a process known as “the Great Work”, involves the putrefaction of lead into its four elements and then the coagulation of these elements into a new substance.

Conclusion

Alchemy is an ancient practice which combines science, philosophy and spirituality in its attempts to unlock the secrets of nature. Over centuries, the practice of alchemy has evolved and been studied by many great minds, from Leonardo Da Vinci to Isaac Newton. Although the practice of alchemy is now generally considered to be pseudoscience, it nonetheless holds within it the possibility for great progress in understanding and manipulating the natural world.

Gold chemistry is the study of the properties and reactions of gold and its compounds. Gold, the most malleable of all metals, has a stunning wide range of applications. It is used in jewelry, electronics, coins, and alloys. Gold has an atomic number of 79, an atomic weight of 196.966569 g/mol, and a melting point of 1,064.18 °C (1,947.52 °F). Gold is a transition metal and is a member of group 11 or IB in the periodic table.

Gold has a variety of oxidation states from -I to +V, but always prefers an oxidation state of +III. Gold typically exists in a rich yellow color, with various shades ranging from dark yellow to light yellow. Gold is slightly soluble in water, and completely soluble in aqua regia (a mixture of hydrochloric and nitric acids).

Gold has no known natural catalysts, meaning it has no catalytic effect on the majority of its chemical reactions. However, it can act as a catalyst in some organometallic reactions, helping to break down molecules. Gold also has some unique oxidation-reduction properties, which involve the transfer of electrons with reduction and addition.

Gold is also important in biological systems, playing a role in the bodies of certain invertebrates and other animals. In humans, gold is used in dental alloys and for certain medical treatments. In the late 1800s, gold was used to treat arthritis and it is still used to treat cancer in some forms.

Gold has the ability to migrate from the surface of a material to the core, discussing en zones of leaching, which allow it to diffuse through porous material. This form of mobility is termed migration. It is also important to note that much of what is known about gold chemistry is based on studies done in the laboratory, which involve gold extraction and its analysis.