Evidence of Vitrified Stonework in the Inca Vestiges of Peru (cont.)
By Jan Peter de Jong & Christopher Jordan
Photo 1: The Vitrified Surface of the Stone
as photographed by the microscope. It shows two distinct regions, the
surface layer and the body stone. There is a less distinct
intermediate area between the two that seems to transition from stone
body to surface layer. Samples from all three regions were subjected
to detailed analysis.
at bottom is 21 micrometer)
Composition of the Surface Layer
Note: The full set of photos, spectra and tables can be found in the full article
body of the stone shows the spectral composition for limestone. High
levels of calcium, carbon, oxygen and minor trace elements are the
constituents of limestone. This is not unusual since the University
of Cusco recognize the Sacsayahuaman archaeological park as being a
karst landscape. Many cave systems are made in limestone bedrock and
the sample was from this sort of cave. However, this cave was worked
on by people in the past as is clear by the photos above.
Vitrified Surface of the stone shows a very different spectrum of
elements to the limestone body. The glaring difference is that
Silicon is the predominant component with much higher concentrations.
The trace elements of Aluminum and Magnesium are also significantly
higher than the body of the stone. Oxygen is also present in double
the quantities found in the body. The quantities of Calcium and
Carbon are much lower than the body sample.
Silicon, Aluminium and Magnesium seem to indicate that a material was
added to the surface of the stone. The oxygen may have been part of
this matter or it may have been introduced as part of oxidation
during an aerobic heating process. This could have been during the
formation of silicate, SiO2.
analysis of the intermediate region between the surface and body of
the stone shows a gradation of compositions. This is a surprising
result, it implies either the surface layer was somehow ground and
mixed with the body of the stone. The body limestone somehow
merged/melted with the surface layer. Lastly and most unlikely, the
limestone constituents could have been a part of the added surface
layer. If this last one were true the second and third spectra would
have been more similar.