Good for another bump.
Many purposes have been discussed about tablet usage including stamping or printing images, use as a whetstone or abrader, medicinal plate or mortar, paint palette, tribal subdivision or moiety insignia, tattoo device, or for use in bloodletting ceremonies with a bone implement sharpened by engraved tablets. Such objects may have functioned as a pneumonic device for staging oral recitations about prestige and power of their patrons culture, recalling national or state history of particular events, mapping tribal and chiefly geography, charting political and social hierarchy, ancestral motifs genealogy, mythical spiritual heroes, powerful weather events such as thunderstorms, or geophysical phenomenon such as earthquakes.
See: http://www.freewebs.com/historyofmonksmound