mexico, at sites such san loren, la venta, tres zapotes near the gulf coast, and tlatilco and chalcatzingo in the highlands. in the 18th and 19th centuries, finely carved jades from mesoamerica began to appear in museums and private collections. no one knew what to make of them. some were labeled chinese, others maya or aztec. in 1862, a farmer's discovery of a he stone head at tres zapotes triggered speculation that it had be carved by africans who haimmigrated the americas. newsre aouncer: pulling it for two hos ov swampland is the last ste of our trip to the spot whe we hope to find the big stone heads of which we have hrd exciti rumors. obregon: archaeologist tthew stirng setutn 1939 tonravel the mystery of these strange works of art, which by then were being called "olmec." sponsored by the smhsonian institut the al raphic s d thifemari to mexico, launching the excavations on the southergulf coast no onenew how old the olmec culture was. many thought it was contemporary or later than tssic maya, w floushed from 300 to 9 a.d. newsreel announcer: and here is our objective: tres zapotes,