I just started re-reading the Epic of Gilgamesh (Penguin Classics edition, translated by Andrew George). In the prologue, the poet says "...pick up the tablets of lapis lazuli and read out the travails of Gilgamesh..." I know that the actual cunieform-inscribed tablets that we have today are made of clay, but I was wondering if there actually were inscribed lapis lazuli tablets. I did some googling and saw that the Ten Commandments are also thought to have been written on lapis. Was this just poetic embellishment? Do any surviving examples of inscribed lapis from the ancient world remain today?
We actually do have a fair number of inscribed objects of lapis lazuli; most of them are seals but we do have a few larger objects such as the following inscriptions of Kurigalzu: http://cdli.ucla.edu/dl/photo/P263468.jpg http://cdli.ucla.edu/dl/photo/P263396.jpg
Having said that, the text of Gilgamesh would likely not have been written on lapis lazuli; that stone was extremely precious in Mesopotamia and had to be imported all the way from today's Afghanistan. Indeed, in inscriptions lapis is often mentioned in the context of other precious materials (see for example this letter which mentions it alongside other precious things: http://oracc.museum.upenn.edu/cams/gkab/P338358/html), so it would really only be used for certain kinds of inscriptions.
The opening lines of the text actually is related to a more common literary conceit, of which another poem called the Cuthean Legend of Naram-Sin is a good example. That poem opens by describing itself as written on a stela(narû) in the foundation of the Emesalam Temple in Kutha and concludes by summarizing its advice as directed to the reader of the stela: "I have written to you a stela/In Cutha, in the E-Melsalam...listen to the wording of this stela"(Foster 1995, 176). The Standard Babylonian epic also mentions Gilgamesh setting down his deeds on a stela, although it does not describe itself as a stela. So by characterizing itself as written on stone(and we can accept the writing of the full text of the poem on lapis lazuli as a sort of poetic exaggeration) and deposited in another valuable receptacle(normally tablets were stored in a reed box rather than a cedar box) the poem presents itself as an example of 'naru literature", that is, literature which is presented as having been written in the past to be handed down and used to educate future kings and scholars, and in this case as recounting a kind of secret or hidden wisdom* gleaned both times (the events of before the Flood) and places (the very end of the known world, to which Gilgamesh voyages) normally inaccessible to humans.
