article_snippet.sent: Some archaeologists believe the toxic element could herald .
article_snippet.sent: may have been used to symbolize an underworld river or lake.
article_snippet.sent: Archaeologists believe it may .
article_snippet.sent: have had a supernatural significance for ritual ends.
article_snippet.sent: of thousands of artifacts including stone sculptures, fine .
article_snippet.sent: jewelry and giant seashells leading to the three chambers.
article_snippet.sent: increases the odds of finding a tomb. '