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I'd like to ask how can one determine /with relative precision/ the age of stones and stone monuments, like statues, columns, stone walls or stone tablets? I know that one determines the age of organic substances by radiocarbon dating, however, this method is inapplicable for rocks, so what else can we try?

Under age I mean the period since a stone was carved into a historical artifact and I'm interested in periods that are accurate up to a historic age, like Antiquity or the Renaissance - I suppose one cannot ask for more, unless there are visual marks on the artifact, which provide clues?

PS I hesitated much whether my question is Chemistry- or Physics- related and decided to post it here, since it's purely practical. If you decide otherwise, I'll move it to Physics.SE ;)

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    $\begingroup$ Are you suggesting that physics is a purely theoretical subject and chemistry a purely practical one? ;) $\endgroup$ – bon Oct 10 '15 at 10:34
  • $\begingroup$ Definitely no. I really struggle to determine the boundaries between sciences. My logic was that in Physics one usually perform experiments to verify Physical laws, while in Chemistry the experiments usually have practical applications like the one I'm interested in... Thus, I think my question is more about Chemistry rather than Physics /maybe I'm wrong, of course :P/ $\endgroup$ – Newbie Oct 10 '15 at 10:37
  • $\begingroup$ What timeframes are you interested in? Ancient rocks are usually dated with radioisotope methods, often using uranium. More modern rocks may use other techniques. $\endgroup$ – bon Oct 10 '15 at 10:41
  • $\begingroup$ I'm interested in narrower time-frames, e.g. centuries or at most millennia. For example, how can we determine whether a statue is from Antiquity or from the Renaissance (assuming there are no erosion and other visual marks on it)? $\endgroup$ – Newbie Oct 10 '15 at 10:45
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    $\begingroup$ Are you asking about the age of the rock since it solidified or recrystallized? This is possible by radiochemical means (e.g. potassium–argon dating). Or are you asking about the age of a statue since it was made from that rock? Depending on the circumstances, this may also be possible by different radiochemical means. $\endgroup$ – user7951 Oct 10 '15 at 10:45
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The question being asked, I believe, is the age of the inscription or statue rather than that of the material from which it is made.

The answer, though, is that it is quite difficult to do on the basis of a single stone object. If it is found in situ, then the age of surrounding items may be a guide.

There are some clues to the age of stone objects, though. For example, if a stone object (e.g. the walls of Siloam's Tunnel) has soot on its surface, such as from torches, then radiocarbon dating shows a minimum age (because the soot could have been deposited some time after the tunnel or object was made).

Weathering of a surface can provide information, providing the object has been exposed to known atmospheric conditions; but a buried statue would erode differently from one on the surface.

For stones, or better, for ceramics, that have been heated, thermoluminescence provides an accurate way to measure age (or at least time since last being heated).

One indication for the age of the Egyptian pyramids is their alignment to a calculated geologic reference that changed with time due to the precession of the Earth.

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Radiocarbon dating is one form of isotopic dating, which is applicable to rocks, and is the basis for huge chucks of geology, archaeology, and astrophysics. How do you think we estimate the age of earth, moon, prehistoric pottery and tools, etc?

There are many ways to do it: thermoluminescence dating, Cl-36 dating (within 50 years of present due to Nuclear weapons testing), U-Th dating(last 500,000 years), Optical dating (100-200,000 years before present), and I-129 dating (recent). These just are the ones I can think of off the top of my head, I'm sure there are many more, and any decent archaeology textbook will have a chapter on the subject if you need more specifics. Any method can be chosen based on what the sample is, how recent it is, and how big it is (ie how much you can destroy to get an answer).

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  • $\begingroup$ I presume you mean that isotopic dating is applicable to rocks? I did a double-take at the first sentence because I thought you meant that we could use radiocarbon dating to date the moon, which would be quite impressive indeed. $\endgroup$ – chipbuster Oct 10 '15 at 20:17
  • $\begingroup$ @chipbuster Clarification: Radiocarbon dating is one form of isotopic dating. Isotopic dating can be applied to many things besides organic matter. $\endgroup$ – Mecury-197 Oct 10 '15 at 22:14

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