U.S. Federal laws governing recovery of treasure are governed by the Archaeological Resources Protection Act of 1979, Under ARPA, "archaeological resources" more than one hundred years old on public lands belong to the government. The term "archaeological resource" means any material remains of past human life or activities which are "of archaeological interest", as determined by federal regulations. Such regulations include, but are not limited to: pottery, basketry, bottles, weapons, weapon projectiles, tools, structures or portions of structures, pit houses, rock paintings, rock carvings, intaglios, graves, human skeletal materials, or any portion or piece of any of the foregoing items. The definition of "archaeological resource" and "archaeological interest" has been broadly interpreted under U.S. agency regulations in recent years to include nearly anything of human origin more than 100 years old, while permits to allow recovery of such items have been largely restricted to digs by credentialed archaeologists. The effect of ARPA as currently defined by federal regulations outlaws virtually all treasure hunting of items more than 100 years old, even treasure troves of gold and silver coin or scrip, under penalty of total forfeiture. Furthermore, the Federal policy against spoliation and removal of "archaeological resources" of any type from federal or Indian lands, even coins and scrip less than 100 years old, means it is unlikely that a finder of gold or silver coinage on Federal lands will prevail with an argument that the find constitutes a treasure trove of coinage, but rather "embedded property" that belongs to the property owner, i.e. the government. The broad use of ARPA to target not only archaeological looting but also to prohibit all treasure hunting on federal or Indian lands has been criticized on the grounds that total prohibition and forfeiture simply encourages concealment or misrepresentation of the age of the found coinage or treasure trove, thus hampering archaeological research, as archaeologists cannot study items that when found will never be reported.