In the early part of his evolution, man made great use of rock and stone to assist him in his activities. The term ‘Stone Age’ has been given to the period of time during which stone was the main material used for the manufacture of functional tools for daily life. It is generally thought to have commenced about 3.3mya and was the time when man firmly established his position on earth as a ‘tool-using’ mammal. However, it should be remembered that stone was not the only material used for this purpose. More perishable materials, such as wood, reeds, bone and antler, were also used, but very few of these materials have survived to be found today (but see the box: Non-stone tools).
A notable exception to the general rule that non-stone tools have not been preserved is the Palaeolithic wooden spear shaft that was recovered in 1911 from a site in Clacton in Essex. At 400,000 years old, the yew-wood spear is the oldest, wooden artefact that is known to have been found in the UK (see http://piclib.nhm.ac.uk/results.asp?image=001066).
A number of wooden spears dating from 380,000 to 400,000 years ago were also recovered between 1994 and 1998 from an open-cast coal mine in Germany (see https://en.wikipedia.org/wiki/Schoningen_Spears). Other items are found from time to time from peat-bog conditions, which offer the most favourable medium for the preservation of such material.
The stones used to make tools
Being a non-perishable material, stone has survived the ravages of time and is therefore the main material from which much of our current knowledge about the history of man has been obtained. The technological development of mankind is known to have proceeded at different rates in different parts of the world, one particular example of this being when early man in Europe were using stone tools at a time when bronze was the material being worked in Egypt and Mesopotamia. A more recent example is displayed by the Aborigines and other native Australian populations of today, who use stone tools that are hard to distinguish from artefacts from European Palaeolithic times.
The ‘Stone Age’ element of our history is usually sub-divided into three periods (each with its own tool culture), the earliest of which is known as the ‘Palaeolithic’ period, otherwise known as the ‘Old Stone Age’. This era began about 3.3mya when stone tools were first used by an early species of human (Australopithecus afarensis). Starting about 20,000 years ago the ‘Mesolithic’ era (the ‘Middle Stone Age’) followed the Palaeolithic period and then, commencing about 10,200 years ago, the Neolithic period (‘New Stone Age’) became the most recent of the three sub-divisions. About 3,500 years ago, the Neolithic period ended and was replaced by the ‘Bronze Age’, this being the time when man discovered the use of metals. However, as will be seen, man has used rock and stone throughout his history.
Only some types of stone are suitable for use in the making of tools and, consequently, early man had to ‘hunt’ for the correct types of stone to use. It was necessary to know what type of stone he was looking for and this requirement can be taken as a sign of man’s evolving intelligence. The most familiar of the stone types in question is flint (Fig. 1), which is a hard sedimentary cryptocrystalline form of the mineral quartz and is a stone that fractures easily and cleanly, producing sharp edges that are capable of cutting flesh (Fig. 2). It can even fracture predictably.
The incisive property of flint was recognised by early man, who made practical use of that property primarily for the acquisition and preparation of food supplies. Flint occurs naturally in sedimentary rocks, including chalks and limestones, and can exist as individual nodules of varying size, large irregular masses and even as sheet deposits, the latter providing welcome mining opportunities in Neolithic times (for example, at Grimes Graves in Norfolk).
Through time, other stone types have been used to make tool artefacts, but not all of these have the same properties as flint. Another silica-rich cryptocrystalline sedimentary stone type that was often used, particularly in the southwest of the UK, is chert (Fig. 3). Although not quite the same as flint in mineralogical terms, chert can be fashioned in a similar manner and has consequently been used in the production of functional tools.
A mineral of igneous origin known to have been used for making tools is obsidian, (see Fig 4). Commonly called ‘volcanic glass’, it is a hard, glassy mineral which fracture easily yielding very sharp edges. This property was noticed by early man, who put it to productive use to make cutting and piercing tools. In modern times, it has even been used experimentally to manufacture surgical scalpel blades.
In the North African desert regions of Libya and Egypt, a large quantity of a natural silica glass, known as ‘Libyan desert glass’, can be found. About 26mya, a meteor fell causing a massive fireball that generated a tremendous amount of heat (at least 1,600oC). Desert sand was blasted into the atmosphere, melting in the heat and then raining back down to earth again as liquid glass, finally solidifying to form the glass fragments that can be found today. The functional qualities of this material became known to prehistoric man about 10,000 years ago and it was successfully used to manufacture tools (Fig. 5).
The Stone Age was followed by the Bronze Age, which saw man’s discovery of metals, these proving to be a dramatic aid to daily life. Tin was mined as an ore (cassiterite) and smelted before being added to molten copper to make the alloy. The ‘Iron Age’ then followed, but it should be appreciated that stone tools were still being used for many purposes during both these periods of time (although their quality noticeably deteriorated).
Types of tool
As Homo evolved, his mental capacity increased such that his manufacture of tools was accompanied by increasing levels of sophistication. Stone tools can be grouped into distinctive patterns of manufacture, each pattern showing an increased level of sophistication over its predecessor. These patterns are termed ‘cultures’ (or ‘industries’) and the culture to which a stone tool can be attributed is one of the indicators that has been used in the past to help identify the species of hominid responsible for its manufacture, an important step in tracking the evolution of man.
Initially, early man made use of sharp edges that can occur on naturally broken pieces of stone and, recognising the value of these artefacts, put them to effective use. However, he then began to create his own sharp-edged fragments through the simple act of banging two stones together in the right manner to produce the desired articles. As time passed, the manufacturing technique was increasingly refined and tools of greater sophistication began to appear.