228 FIELD CoLumMBIAN MustEuM—ANTHROPOLOGY, VoL. II. 
OBSIDIAN. 
It is evident, judging from the specimens found, that obsidian 
was a rare material in Yucatan. During my ten years’ investigations 
among the ruins of Yucatan and Campeche, I have not found as many 
specimens of worked obsidian as I picked up in half an hour between 
the Temples of the Sun and of the Moon at San Juan Teotihuacan, 
Valley of Mexico. The reason for this is plain. At San Juan we 
were in the vicinity of rich deposits of obsidian. From the banks of 
the river the natives could almost point out the cliffs in which it is 
found, while in the river bed we observed water-worn pebbles and 
masses of obsidian, resembling lumps of coal. 
At Xkichmook and elsewhere in Yucatan I have never found a 
single obsidian implement, except the slender flakes that probably 
served as knife blades; these are rather fragile for the ordinary uses 
of a knife, but some are so sharp that when dexterously used they will 
cut or even shave a beard. 
STONE IMPLEMENTS. 
In no other group of ruins have I found such plentiful traces of 
the ancient fabrication of flint implements as at Xkichmook. There 
does not appear to have been any large bodies of material from which 
these weapons were made, but loose, rounded, cobble-like masses of 
chalcedony, some a clear snow-white, others of pearly and pinkish tints, 
were utilized. I found sometimes quite a quantity of these nodules 
collected together, and close by were small heaps of chips and rejects, 
the latter representing all stages of implement development, These 
chalcedony lance and arrow heads are often skillfully chipped and 
very handsome. Examples of the flaked implements appear in Pls. 
XXIII and XXIV. 
With the exception of a celt fragment made of nephrite, and the 
cylindrical mealing-stones illustrated in Pl. XXV, I did not find a 
single polished stone implement at Xkichmook. 
