Flaked obsidian C.800 BC-800 AD. Valley of Mexico, probably Teotihuacan, 4” length, barbed leaf form. Fully evolved construction with both faces completely flaked as opposed to the earlier, mono faces with one side showing a large single cleavage. Beautifully worked with traces of soil adherence from burial. The Valley of Mexico which contains modern Mexico City is surrounded by volcanic mountains, the issue of which formed the obsidian from which weapons were produced.