Collection place
- O'ahu, Hawaiian Windward Islands, Hawaiian Islands15 objects
- OR-KL-NL-1, Klamath County, Oregon6 objects
- OR-KL-NL-2, Klamath Falls, Klamath County2 objects
- OR-Morrow-NL-1, Morrow County, Oregon2 objects
- OR-Morrow-NL-2, Heppner, Morrow County, Oregon2 objects
- OR-Wasco-NL-1, Wasco County, Central Oregon3 objects
- OR-Wasco-NL-2, Wasco County, Central Oregon37 objects
- Oakland, Alameda County, California92 objects
- Oakley, Contra Costa County, California7,409 objects
- Oakmont area, Sonoma County, California288 objects
- Oakside Ranch, Bolinas, Marin County1 objects
- Oakville area, Napa Valley, Napa County1,936 objects
- Oatman Plateau, Maricopa County, Arizona1 objects
- Oaxaca City, Oaxaca, Mexico18 objects
- Oaxaca market, Oaxaca City, Oaxaca, Mexico9 objects
- Oaxaca, Mexico520 objects
- Obiama village, Bayelsa, Nigeria6 objects
- Obulco (ancient place), Hispania Ulterior2 objects
- Ocangalla (PV 69-29-31), Nazca Valley, Nazca Province1 objects
- Occidental, Sonoma County, California1 objects