92 EXPLORATION OF BURTON MOUND [BTH. ANN, 44 
RUBBING STONES 
The rubbing slabs of coarse sandstone, of which we found several 
good examples, were evidently obtained at the Santa Barbara mesa, 
west of the Burton Mound, where the formation occurs in quantities. 
They were useful for grinding shell, bone, and stone, but there is 
no way of proving what objects were ground on these particular 
specimens. 
Rubbing stone of coarse gray sandstone, friable and gritty; 363.5 mm, long, 
127 mm. wide, 34.9 mm. thick. All edges rounded. The obverse shows espe- 
cially a broad longitudinal depression varying in width from 95.2 mm. to 1383.3 
mm. the deepest part of this groove being 9.5 mm. in depth. The groove 
exhibits in part a more buff color than the remainder of the surface, owing to 
its penetrating a different formation. The obverse shows two narrower longi- 
tudinal grooves of similar appearance. This is the largest rubbing stone. 
Rubbing stone of greenish gray sandstone, not very coarse but friable ; 139.7 
mm. long, 106.3 mm. wide, 25.4 mm. thick. Both ends are fractures. The long 
edges are rounded. The obverse surface presents a wide longitudinal depression 
and has numerous flecks of asphalt. 
Rubbing stone of gray sandstone, very fine textured; 130.1 mm, long, 79.3 
mm. wide, 50.8 mm. thick. The edges are square fractures. Obverse and 
reverse surfaces present natural longitudinal ridges and depressions. 
Rubbing stone of gray, fine-textured sandstone, quite hard; 180.9 mm. long, 
158.7 mm. wide, 88.9 mm. thick. The edges are rounded with the exception 
of the diagonal edge, which seems to be a more recent break. A natural 
groove 69.8 mm. wide and 36.5 mm. deep runs longitudinally along the obverse 
surface. The reverse surface is flat. (Pl. 15, a.) 
Rubbing stone of very coarse, somewhat greenish gray friable sandstone; 
307.9 mm. long, 234.9 mm. wide, 92 mm. thick. A depression varying in width 
from 127 mm. to 165.1 mm runs across the middle of the slab. The surface of 
this depression shows coarse irregular diagonal scatches. The reverse has:a 
prominent longitudinal ridge and shows no sign of use. The edges are mostly 
fractures. (PI. 15, ¢.) 
Rubbing stone of smooth textured gray sandstone, 196.8 mm. long, 142.8 mm 
wide, 41.2 mm. thick. A depression 101.6 mm. wide runs longitudinally across 
the obverse. The ends are square fractures, the side edges are naturally 
rounded. The reverse is flat. (Pl. 15, 0.) 
FRAGMENT OF GILSONITE “ PENCIL” 
Worked cylindrical piece of white material identified as gilsonite; 18 mm. 
long, 3.5 mm. diameter. Unbored. The small end seems to have an older break 
than the larger end. Mr. F. W. Hodge, of the Museum of the American Indian, 
who happened to see the specimen, says that it suggests to him the medicine 
pencils used by the Zunis for rubbing paining parts. (Pl. 16, a.) 
QUARTZ CRYSTALS 
Quartz crystals of various sizes were used by the Indians for sur- 
mounting ceremonial wands of bone or as pendants, asphalt being 
applied to one end of the crystal for attachment. Several of these 
crystals were found in the excavations. The crystals are of what is 
