The Efficacy of Flint Versus Bronze Chisels in Ancient Egypt

Introduction

Flint is a hard stone, made from the silica shells of marine animals (Aston et al 2000:28). In an Egyptian context ‘flint’ and ‘chert’ are often used interchangeably with the delineation between the two being down to the colour, with chert being more brown and flint being more grey (Aston et al 2000:28). For simplicity, this article will use the term flint. Flint’s use in tools and weapons dates to the Paleolithic and Neolithic periods in Egypt, and its use continued well into the Dynastic period, with excavations showing royal tombs of the 18th to 20th Dynasties were created using flint hammerstones and chisels (Aston et al 2000:28-29)

Bronze is an alloy of copper and tin (Ogden 2000:153). It began to be used in the late Predynastic period, and its use continued into the Dynastic period before it was eventually replaced with iron and steel (Arnold 1991:257). Odler (2016) also argues that arsenic copper was used exclusively in the Old Kingdom. Molten copper and copper alloy can be poured into moulds to rapidly create tools and weapons. Both bronze and copper will work harden, and require hammering to create the most durable cutting edges on tools and weapons (Davies & Laboury 2020:117).

Figure 1 – De-correlation stretch of Manchester Museum 4906, highlighting the red colouration of the ears

Whilst entire books have been produced on Egyptian copper and copper alloy tools (Odler 2016; Petrie 1917), there is very little material published on flint chisels, however Stocks (2003:81-95) does discuss their use for carving larger hieroglyphs (Stocks 2003:87) and their use for working hard stones such as granite (Arnold 1991:264; Stocks 2003:82) which could not have been worked using bronze.

To test the efficacy of chisels made from both materials for small detailed work, a bronze and a flint chisel were created by the author and used to create a limestone replica of an Ancient Egyptian New Kingdom (c. 1550-1069 BCE) based on Manchester Museum 4906 (Figure 1).

Apparatus

The flint chisel was created using traditional methods, by taking a small bifacially flaked flint blade and mounting it into a wooden handle which was bound together using natural cordage and sealed with a beeswax and carbon adhesive (in an approximate 50:50 ratio). The cutting edge of the flint chisel was 13 mm wide with a 0.7 mm edge.

The bronze chisel was formed by cold-forging a 5mm bronze rod with a modern steel hammer and anvil which was then friction-mounted into an oak (Quercus robur) handle. The cold working caused the material to work harden, and the edge was given additional hammer hardening. The edge was hand-beveled and sharpened using a modern diamond file to produce a sharp cutting edge. The cutting edge of the bronze chisel was 5.9 mm wide with an edge of under 0.1 mm.

Method

Figure 2 – Hieroglyphic design for replica ear stelae

Hieroglyphs (Figure 2), representing Ptah-hearer-of-prayers (ptH sDm-nH<w>) between two ears and a lower register representing Made by Matt (ir n mAt),were laid out on two 95 x 75 x 5 mm sections of limestone using pencil. These two different stelae were then carved created, one with each chisel.

Both chisels were driven with a flat river pebble, using their thin edge to follow the pencil guidelines.

Results

Figure 3 – Flint chisel being used to carve limestone ear stela

The flint chisel (Figure 3) did not suffer any damage and did not need its edge sharpening and removed limestone with ease. This replicates the results found by Stocks (2003:83) The only issue which affected the performance of the chisel was due to its manufacture; the blade was far too short and this inhibited the ability to see the lines clearly and the cord and beeswax wrapped caused fouling at lower angles, which forced the chisel to be used in higher angles compounding the obstruction of the guidelines.

Figure 4 – Bronze chisel being used to carve limestone ear stela

The bronze chisel (Figure 4) was initially sharper than the flint and cut cleaner lines in a faster time. However, it very quickly dulled, and its thin edge began to roll – especially on the corners of the blade. To be effective the chisel required constant maintenance. The long neck of the chisel allowed it to be used at a variety of angles and gave a clear unobstructed view of the guidelines.

Conclusion

Figure 5 – Completed replica ear stela

Both materials can be used to produce detailed carvings (Figure 5), however the flint chisel demonstrated advantages over the bronze chisel.

Whilst flint is a brittle material, using it as a hammer stone driven chisel did not cause any issues or affect its edge or integrity.

Flint was always present for use in tool making, even when access to metal tools was temporarily restricted (Stocks 2003:82). The microliths required for the chisels can be created very quickly and easily, and spoil from other flint knapping could be recycled into chisel blades – making them extremely time and labour efficient to create.

The bronze chisel performed significantly worse in the test than the flint chisel, with its edge blunting and curling very quickly. The edge curling of bronze chisels has been observed by masons studying the dressing of pyramid casings, and it’s estimated that a dedicated chisel sharpener was required for every 100 workmen (Lehner 2008:211). It is less critical for a fine edge when dressing a pyramid’s casing stones than it is for fine carving tasks, where it is extremely impractical to be constantly swapping or sharpening chisels.

When the performance of flint versus bronze for cutting small lines and performing detailed work, it appears that flint holds the advantage; it is an abundant resource and so cheap and easy to produce flint chisel blades, flint does not deform or break during carving use, and it is capable of working hard materials. It therefore seems likely that flint chisels played a much more significant role in Ancient Egyptian stone working than is typically discussed.

References

Arnold, D., 2008. Building in Egypt. New York: Oxford Univ. Press.

Aston, B., Harrell, J. and Shaw, I. (2000). Stone, in P. Nicholson and I. Shaw (eds.) Ancient Egyptian Materials and Technology, pp. 5–77. Cambridge: Cambridge Univ. Press.

Davies, V. and Laboury, D. (2020). The Oxford handbook of Egyptian epigraphy and palaeography. Oxford University Press.

Lehner, M. (2008). The complete pyramids. London: Thames & Hudson.

Odler, M. (2016). Old Kingdom Copper Tools and Model Tools. Archaeopress Archaeology.

Ogden, J. (2000). Metals, in P. Nicholson and I. Shaw (eds.) Ancient Egyptian Materials and Technology, pp. 148–176. Cambridge: Cambridge Univ. Press.

Petrie, W. (1917). Tools and Weapons. London: British School of Archaeology in Egypt College, University College.

Stocks, D. (2003). Experiments in Egyptian archaeology; Stoneworking technology in ancient Egypt. London: Routledge.

Highlight-Based RTI Equipment

The equipment required for highlight-based Reflectance Transformation Imaging (RTI) is essentially the same for all captures; a light source which can be moved (or a dome of multiple light sources) and a fixed camera perpendicular to the object being imaged. However the actual objects being studied do inform the exact choice of equipment. My current work is on Ancient Egyptian Predynastic palettes, as my next research project will be too, which typically are around 20-40cm (even the so called Narmer palette is only 64cm in its longest dimension). If you’re working with larger objects then some of my problem solving wouldn’t fit your needs.    

Figure 1 – H-RTI flashgun setup

Typical highlight-based RTI (H-RTI) setups use a string tied to the flash to ensure a constant distance between the head of the flash and the surface of the object. Rather than put string onto the flash which needs measuring for each set up (and can untie itself during capture and need more measuring), I’ve mounted a 1.50m (60 feetsies for my American colleagues) fabric tape measure with a plastic tip. It’s mounted to the flash on the underside by Velcro to a Honl SpeedStrap, but you could just use any Velcro mounting onto the flashgun. Whilst string gives you more versatility and distance, for the smaller objects I am currently studying this solution gives me a few less steps in setup – which an RTIsta will tell you takes much longer than the capture itself and any streamlining is welcomed. I found two minor issues with the tape measure set up when I first used it. Firstly the tape measure needs to be set back slightly from the front of the flash, or it interferes with the light spread, and secondly the black plastic tip is extremely hard to see in low light environments – thankfully something easily remedied with a piece of white plastic tube glued onto the tip.  I had toyed with the idea of having two laser dots to line up to get the correct distance, somewhat like a modern Dambusters, or even using an ultrasonic rangefinder but decided that simple was better. Although if/when I work on larger objects and need to be further away I might revisit the ultrasonic rangefinder idea instead of using metres of string.   My lighting setup is using an Olympus FL-35 flash and Phottix Atlas triggers, for no reason other than I already owned them. Any flash which allows the setting of light intensity setting and remote trigger, or continuous lighting, set up will work.  

Figure 2 – Engraved Thoth hieroglyph

The grip is a motorbike grip over a solid aluminium round bar, which was drilled and tapped to accept a ¼ inch (20 TPI) male to ¼ inch (20 TPI) male connector that then screws into the trigger unit. I don’t have access to a lathe, or it would have been nice to have turned the end of the bar down and threaded it to screw into the trigger (similar to the handle supplied in the CHI starter kit). The aluminium bar was chemically blackened and I’ve hand engraved a Thoth hieroglyph into the end of the bar (Figure 2).    

Figure 3 – Quick release camera mounting bracket, on adjustable copy stand column

My museum based research is on smaller objects and often in location where it’s not possible to set up a large stable tripod, and so a copy stand is much more suitable as it has a significantly smaller footprint. Traditional copy stands usually have their own baseboard and potentially their own legs, making them less ideal for transport to different research locations, and they also tend to be rather expensive. To mitigate both issues I’ve built myself a mobile copy stand which has a desk clamp rather than the traditional style stand (Figure 5).   This stand is built from a Dusrt M670 darkroom enlarger column and base with a compatible geared winder, mounted to a computer monitor stand desk clamp. The horizontal camera arm (Figure 3) was created with a 150mm long mild steel tube with a 25mm internal diameter, with an M6 wingnut style hand knob bolt to secure it to the winder and with a solid mild steel plug interference fitted into the end (with a 4mm grubscrew to ensure zero possible movement) which was drilled and tapped to ¼ inch UNC (20 TPI) and bolted to a Manfrotto quick release mount. Using the ¼ inch UNC (20 TPI) thread makes the unit compatible with standard photography equipment, such as tripod heads or camera brackets.  

Figure 4 – Desk clamp

The column was mounted to a desk clamp (Figure 4) using a 5mm thick mild steel interface bracket, which both clamp and column base were bolted to. This then allows the whole unit to be camped onto a desk, with the camera height being easily adjusted.

Figure 5 – Copystand with camera mounting bracket

Analysis into Predynastic Ancient Egyptian Malachite Processing and the Production of Microfibres

Figure 1 – Malachite processing using stone hammer against a sandstone block

The 19th century description of ‘grinding malachite’ to reduce it to powder for pigment is completely erroneous, and effective processing requires smashing or crushing – most likely with a hammer stone against an substantial anvil stone as shown in Figure 1 and also in video demonstration here: http://www.instagram.com/p/BksM2HQgT-s/

This percussive smashing and crushing produces small crystal shards which are extremely flyable. To contain these, the malachite would be wrapped in a material such as leather or linen. This material would most likely be scrap from clothing or other use, as it is destroyed during the crushing process. This destruction of the wrapping material imparts microfibres, with diameters ranging from 8μm to 23μm, into the resultant powdered malachite as can be seen in Figure 2.

Figure 2 – Powdered malachite viewed at 100x through a Dino-Lite AM4113T, with measurements taken in DinoXcope

The powdered malachite would be mixed with a base before use, such as a lipid base for use in ‘cosmetics’. The presence of the microfibres may help to reinforce the resulting pigment, thus helping to reduce shrinkage and cracking in a manner analogous to the reinforcement of  mudbricks with straw

This microfibre reinforcement may be a part of why green pigmentation appears to survive extremely well on the surface of palettes in the Predynastic era and also in the later Dynastic era (as can be seen in Figure 3).

Figure 3 – Decorrelation stretch vs ‘normal’ photograph of C. 1545 in the Museo Egizio


Steps to Create a Fish-Shaped Predynastic Ancient Egyptian Palette

This is an excerpt from my upcoming paper discussing the manufacture and use of Predynastic Ancient Egyptian palettes, highlighting the various steps which are required to create a fish-shaped (pisciform) palette. The replica was made from slate rather than siltstone/greywacke, as the material was easier for me to obtain. The steps are essentially the same but as slate is softer (Moh 3-4 vs Moh 6-7) it would take longer to create out of siltstone/greywacke and be potentially more abrasive to the tools.