Saturday, June 27, 2020


Keyhole Sink, Kaibab National Forest. Photo Kaibab National Forest.

Keyhole Sink panel. Photo Kaibab National Forest.

A sad incident of vandalism occurred at Keyhole Sink, in Arizona's Kaibab national Forest occurred in August 2010. Some hero (or heroes) with a can of silvery-white paint added their work to a petroglyph panel. 

Keyhole Sink panel vandalized. Forest. Photo Kaibab National Forest. 

"Keyhole Sink is a canyon in the shape of a keyhole near Williams, Arizona. The canyon is best known for its petroglyphs, which were created about 1,000 years ago by the Cohonina people, and the seasonal waterfalls that flow into the canyon." (Wikipedia)

Restoration crew with wire brushes. Photo Kaibab National Forest.

In November, 2010, a team of National Forest personnel led by rock art restorer Johannes Loubser and Kaibab National Forest archaeologist Neil Weintraub performed a restoration on the panel. Several materials and techniques were tested before they decided on their final strategy.

Restoration crew with butane torch and Munsell chart. Photo Kaibab National Forest.

According to Weintraub "for thousands of years and for thousands of visitors - both recent and prehistoric - Keyhole Sink was a serene place to make a connection with nature and the past. I feel that all changed in late August when someone decided to hike in three-quarters of a mile to the petroglyph panel with a bucket of paint." (Banks 2010)

Restoration crew spraying Elephant Snot.
Photo Kaibab National Forest.

The process that they used to remove the paint involved both chemicals and heat. The paint used was an aluminum roofing cement and much of that could be removed from the background rock surface (not the petroglyphs proper) with butane torches. Within the lines of the petroglyphs the butane torches were used to heat "very fine steel brushes just enough to get the brush to help us peel back the paint." (Weintraub 2019)

Keyhole Sink panel after restoration restoration.
Photo Kaibab National Forest.

Remaining traces were removed with a biodegradable cleanser marketed under the name of Elephant Snot. "In 2013, we used our Youth Conservation Corps crew of local high school students to use 'Elephant Snot' to clean up the mess created by the vandals. It worked beautifully and visitors can no longer tell that the site was vandalized. 'Elephant Snot' is a biodegradable cleanser that works on certain paint materials better than others. We have had great success with it, especially in our volcanic landscape." (Weintraub 2019)

I am pleased to note another successful rock art restoration, as well as the materials and techniques used in this endeavor. Another marvelous job.

NOTE: The images in this posting were provided by the Kaibab National Forest. I wish to thank South Kaibab Zone archaeologist Neil Weintraub for his cooperation with RockArtBlog in providing this information, and for the good work of restoring this site. For further information on these reports you should read the original reports at the sites listed below.
NOTE: The weird effects in some type are the result of changes Blogger has made in their style and formatting. As they do not have an instruction manual it may take me some time to master these. Please bear with me. 


Banks, Jacqueline
2010 Vandalized Keyhole Sink Petroglyph Panel Receives Restoration Work, Kaibab National Forest News Release, November 19, 2010

Weintraub, Neil S.
2019 Personal Communication, December 6, 2019.


Saturday, June 20, 2020


Australian mud wasp, Sceliphron laetum.

And while we have been on the subject of rock art in Australia - mud daubers (wasps) have long been a friend to potters as a guide to good deposits of local clays they can use to produce their pottery, now they are becoming recognized as friends to Australian rock art researchers as a source of potential dating for rock art panels.

Not so much a new technique, but a new source of datable material has been found in rock art panels in Australia - mud wasp nests. Made from mud found locally by "mud dauber" wasps, the nests are assembled with cells for the incubation of the offspring, then filled with stung and paralyzed insects for food and a single egg by the female wasp. A mud wasp nest on top of a painted rock art panel will have to have been made after the rock art was created, and if paint is found on top of the remains of an earlier mud wasp nest that nest is older than the painting. If there are a number of nests, and they can be dated, the oldest date from on top of the paint will establish a minimum age range for the rock art (this could be true for petroglyphs as well). A range of maximum and minimum dates can be determined if there are nests found both over and under the painted image. If found in a protected location such as a rock shelter, a mud wasp nest can last a very long time indeed.

Gwion style rock art with mud wasp nest remnant. A) location, and B) close-up.

How can a mud wasp nest provide dating you ask? There are currently two possibilities; AMS 14C dating, and optically-stimulated luminescence (OSL). For AMS 14C dating small bits of organic matter in the dried mud are extracted and dated with an accelerator mass spectrometer (AMS), and the OSL dating is done on small grains of quartz sand included in the dried mud.

Photographig mud dauber nest on rock art,

"OSL is a light sensitive signal that builds up over time during a period of 'burial' or cover. Provided the samples are not exposed to light during collection the signal can be stimulated in laboratory conditions and measured. When divided by the natural radioactivity of the soil or substrate, the amount of light (luminescence) produced is proportional to the period of burial time. OSL is the main method used for establishing chronologies for excavated occupation deposits that pre-date the maximum AMS 14C boundary, or in deposits that lack ample carbon samples. Samples of sediments found within the cave environment have no direct association with the art, but sediments may be collected by wasps and then 'buried' within mudwasp nests found on top of the art. Dating of mudwasp nests using OSL was first introduced by Roberts et al. They initially worked with large nests and sampled each layer to determine the extent to which light no longer penetrated the nests and the quartz was effectively 'buried' and supported their OSL age estimates with AMS 14C or organics found within two nests (Roberts et al)".

As mud dauber wasps are found pretty much all over the world this tool may provide valuable information in many instances where rock art is otherwise undatable.

NOTE: Some images in this posting were retrieved from the internet with a search for public domain photographs. If any of these images are not intended to be public domain, I apologize, and will happily provide the picture credits if the owner will contact me with them. For further information on these reports you should read the original reports at the sites listed below.


Roberts RG, Walsh GL, Murray A, Olley J, Jones R, Morwood MJ, et al.

1997 Luminescence dating of rock art and past environments using mud-wasp nests in northern Australia, Nature, 1997; 387 (6634): 696-699.

Ross, June, Kira Westaway, Meg Travers, Michael J. Morwood, and John Hayward,

2016 Into the Past: A Step Towards a Robust Kimberley Rock Art Chronology, August 31, 2016, Plosone,

Saturday, June 13, 2020


Stenciled crab, Photo
Brady et. al., 2020, p. 7, Fig. 4-9

The creation of rock art images with pigment and stenciling is fairly common in panels of handprints. There are also instances in Australian rock art of images made by holding an object against the rock face and spraying paint around it. These are often images of boomerangs or throwing clubs. Now, a new type of stenciled image has been discovered in Australia. Small images of animals, boomerangs, and humans have been discovered at a rock shelter named Yilbilinji 1, in Limmen National Park in the southwest Gulf of Carpentaria region in northern Australia. "Traditionally owned by the Marra Aboriginal people, the site was documented by the research team in 2017 and instantly stood out as unique, according to the researchers from Flinders University and the Monash Indigenous Centre." ( 2020)

Stenciled anthropomorph with a
boomarang, Photo Brady et. al.,
2020, p. 7, Fig. 4-6.

The authors of the study described it in their published report. "In 2017, as part of an ongoing rock art recording project in northern Australia's south-west Gulf of Carpentaria, a unique and distinctive assemblage of miniature and small-scale stenciled motifs consisting of anthropomorphs, boomerangs, macropod tracks, and geometric and linear designs was recorded from the Yilbilnji rockshelter, traditionally owned by the Marra Aboriginal people, in Limmen National Park." (Brady et al. 2020:2)

Stenciled long-necked turtle, Photo Brady et. al., 2020, p. 7, Fig. 4-10.

The real question is what material and techniques were used to make the stencil. We traditionally think of stencils as particular shaped openings in a sheet of some material that paint can be applied through. This sort of stencil used on a rock face would show considerable edge bleed at rough spots on the edges of the image, yet these particular small motifs show generally sharp and clear edges. The assumption has to be that they used a flexible material that somehow adhered to the surface while paint was being applied.

Stenciled macropod tracks, Brady et. a., Photo p. 8, Fig. 5-12.

As the authors described it - "Morphologically, most of the assemblage comprises motifs with well-rounded or curved edges. These attributes suggest that a malleable substance, such as wax, resin or clay, was used to sculpt the templates, and also to allow the creation of curved but also sharper edges and points, where required. . . . Additionally, with a malleable raw material, a shaped object can be placed flush against an uneven rock wall surface resulting in a more complete reproduction through stenciling. In addition, an adhesive, malleable material would not require support to hold it against the rock wall." (Brady et al. 2020:8-9)

Beeswax test stencils, Photo Flinders University.

Test stenciled panel, Photo

The authors concluded that the malleable material in question was probably beeswax, commonly used by Aboriginal peoples for a large number of purposes. Procuring an actual sample of the native beeswax from Aboriginal sources they tested its efficacy. Small (miniature) shapes were replicated and used as stencils on a sandstone surface using kaolin mixed with water to a paint consistency and then flicked onto the surface from a brush. The beeswax was then removed leaving the negative images.

"In each case, the sculpted beeswax templates allowed for a direct or close replication of the original motifs. Both the sharply defined edges and the curving and angular shapes were easily reproduced in our experiment. The heating and shaping of the beeswax required minimal time or effort, and was an effective and expedient way to create miniature or small-scale stencil motifs on a sandstone rock surface. In addition, the variable rock surface, both smooth and rough, played no role in the model's ability to adhere, suggesting that this technique would be suitable in a variety of different contexts." (Brady et al. 2020:12)

Although no analysis of the rock surface for wax residue was attempted the authors hope to be able to conduct that study in the future. This interesting paper provides useful information Australian Aboriginal rock art as well as introducing a relatively unknown technique they used to create stenciled rock art. Perhaps other parts of the world should also be examined for traces of such techniques.

NOTE: Images in this posting were retrieved from the internet with a search for public domain photographs. If any of these images are not intended to be public domain, I apologize, and will happily provide the picture credits if the owner will contact me with them. For further information on these reports you should read the original reports at the sites listed below.


Brady, Liam M., John J. Bradley, Amanda Kearney and Daryl Wesley,

2020 A Rare Miniature and Small-Scale Stencil Assemblage from the Gulf of Carpentaria: Replication and Meaning in Australian Rock Art, Antiquity,,

2020 Miniature rock art expands horizons,

Saturday, June 6, 2020


Stamped hand prints,
Cave of 100 Hands,
Fremont Indian State Park,
Sevier County, UT. Photo
Peter Faris, 28 May 1992.

When I was going through US Army Basic Training in 1965 at Fort Leonard Wood, Missouri, the new trainees were classified as being either "right-handed" or "wrong-handed". This was because our rifle of issue was the M-14, and the ejection port for the fired empty cartridge was placed in a location that a left or wrong-handed shooter would sometimes get hit in the nose with an ejected, very hot, empty cartridge. Indeed, "A study at Durham University - found that left-handed men were almost twice as likely to die in war as their right-handed contemporaries. The study theorized that this was because weapons and other equipment (were) designed for the right-handed." (Wikipedia) I mention this as an introduction to the question of handedness in rock art. Does the dominant hand leave any clues in the image being created, does it make any difference in the art itself?

Lower-left to upper-right slant,
Picketwire Canyonlands,
Las Animas county, CO. Tracing
by James Keyser and Mark Mitchell,
Photograph Peter Faris.

The basic motions used in the creation of rock art are; Flexion (bringing two body parts closer together, such as the forearm and upper arm), and Extension (increasing the space between two body parts as in straightening the elbow), as well as rotation of the arm and hand. These would cover the production of most examples of rock art. The natural easiest motion of the arm would arc between upper left to lower right and back for the left arm, and from upper right to lower left and back for the right arm. Thus, there might be clues in the orientation of images or the axis in a rock art panel caused by this fact. By axis of the rock art panel I refer to the center line of a unified composition. If individual images are added to the rock face at different times (a newspaper rock for instance) then this would not apply, but if the artist created an overall composition of many elements then the axis (center line) might slope to follow this arc of convenient arm motion. If not the center axis of the panel perhaps a slant to many of the elements of the panel might indicate that same thing. For instance: in 5LA8464, the Box Canyon site in Picketwire Canyonlands, Las Animas county, Colorado, recorded in September 1999 by a crew led by Dr. James D. Keyser and Dr. Mark Mitchell, a large elk and three of the four largest horses in the composition angle upward from lower left to upper right. This would be the natural arc of motion for a right-handed artist.

Upper-left to lower-right slant.
Keyser and Minick, 2018,
Horse Raiders in the Missouri Breaks:
Eagle Creek Canyon Petroglyphs,
Fig. 17, p. 26.

An example that might suggest a left-handed artist is a panel from Montana (illustrated in Horse Raiders of the Missouri Breaks by Keyser and Minick) which includes three equestrian figures, all of which display an upper left to lower right slant. This question of orientation of figures, or panels, providing clues to handedness is probably too weak to base assumptions on by itself, but when found with other clues can, perhaps, be considered a reinforcing argument.

Horse legs, Gargas Cave,

According to Bahn and Vertut there are also clues to handedness that can be found in the preferred lighting of rock art panels. "In most cases, fine engravings are almost invisible when lit from the front, but 'leap out' when lit from the side. This fact is of some importance, for it provides an indication of whether the artist was right- or left-handed. Right-handed artists tend to have their light source on the left, to prevent the shadow of their hand falling on the burin (or brush), and accordingly the majority of Palaeolithic parietal engravings are best lit from the left (in portable engravings, too, the proportion of right- and left-handers is similar to that of today). Occasionally, however, one comes across the work of a southpaw - for example, the Pyrenean cave of Gargas has many engravings including a fine, detailed pair of front legs of a horse; these had been known and admired for decades; but one day, when visiting scholars lit the figure from the right instead of the left, they were suddenly confronted with the rest of the horse, which nobody had seen before! It is possible, of course, that Palaeolithic artists used the lighting of engravings to their advantage, making them appear or disappear to great effect - alas, we shall never know." (Bahn and Vertut 1997:108)

Sprayed handprints, internet
photo, public domain.

Also, if one hand is used in handling pigments or tools used to create rock art, we can assume it to have been the dominant hand. If this is the case then we may be able to make assumptions on handedness from the handprints that are so common in rock art. If the print is a direct stamping,  i.e. pigment applied to the hand and then stamped on the rock surface, then it was probably made with the dominant hand. If it is a patterned stamped handprint, then the paint was probably applied with the dominant hand to the other hand which was then stamped on the rock. An outlined handprint, I will assume, is made by using the dominant hand to draw around the other hand held to the rock surface. An orally-sprayed handprint could well have been made with either hand.

Gower Cave rock art, Swansea,
South Wales, Britain.
Dr. George Nash.

Another example of evidence of "handedness" in rock art is illustrated by the discovery of a reindeer wall engraving in a cave in South Wales in Britain by Dr. George Nash from the University of Bristol. "Dr. Nash discovered the faint scratchings of a speared reindeer while visiting the Gower Peninsula caves near Swansea in September 2010. - This drawing appears to have (been) engraved by an artist using his or her right hand as the panel on which it is carved is located in a very tight niche." (Heritage Daily 2011) So the handedness of this artist can be deduced by the location of the image itself. In this case it must have been on the left wall of a narrow niche so that only the right hand could conveniently access it.

So, does any of this matter? Who cares whether the people producing rock art were right or left-handed? Well, aside from anthropologists who love this sort of thing, it provides us with tangible evidence that the people who produced the rock art were pretty much just like us. And, that being the case, perhaps we can more appreciate their thoughts and beliefs.

NOTE: Some images in this posting were retrieved from the internet with a search for public domain photographs. If any of these images are not intended to be public domain, I apologize, and will happily provide the picture credits if the owner will contact me with them. For further information on these reports you should read the original reports at the sites listed below.


Bahn, Paul G., and Jean Vertut,
1997 Journey Through The Ice Age, University of California Press, Los Angeles.

Heritage Daily,
2011 Archaeologist's Chance Discovery May Be Britain's Earliest Example of Rock Art,

Keyser, James D., and David L. Minick
2018 Horse Raiders in the Missouri Breaks: Eagle Creek Canyon Petroglyphs, Montana, Publication #25, Oregon Archaeological Society, Portland.