Joseph Dorenberg, the German Consul who lived at Puebla, Mexico in the 1890s, purchased an ancient skull which he took back home with him to Leipzig, Germany. After his death it was donated to the Museum für Volkerskunde in 1919 and put on display.
However during World War II, the museum and surrounding areas were leveled by a RAF bombing (Dec. 1943), and the skull was destroyed with most of the museum’s contents.
Diatomaceous earth is a sedimentary rock that is made up of the fossilized remains of diatoms, a group of unicellular algae. The most remarkable feature of diatoms is that they are encased within a small “shell” or capsule made of silica, which when the cell dies, drops to the sea bead and accumulates. The different varieties of fossil diatoms found in Diatomaceous earth allow scientists to date them and remains that are found buried by it.
This came in handy as the “Dorenberg skull” was found buried in diatomaceous earth. Hugo Reichelt, of Leipzig took some samples of the diatomes and established the skull’s age. His study was published in an article  and the skull was pronounced as “antediluvian” (i.e. before the last Ice Age). 
He kept some samples of the diatomaceous earth which was reanalyzed recently using modern techniques  and found that these diatoms: “ indicate an age corresponding to the Sangamonian Interglacial sensu lato (80,000 to ca. 220,000yr BP).” 
This is long before the accepted date of modern human entry into America. Furthermore, the heavy and prominent brow ridges and the sloping forehead are very unlike Homo sapiens yet very similar to H. erectus. This is a clear proof of erectus in America some 80 - 220 kya.
It is a shame that the "solid" proof (the Dorenberg skull) has been lost.
Some orthodox scientists in an attempt to discredit the finding have insinuated that the whole Dorenberg skull story is a hoax: "In relation to the Dorenberg skull, the reviewer claimed that, "... (there is evidence that this was a hoax generated by Europeans...". 
 Patrick Lyons. Pleistocene America. Online. Also see The mystery of the Dorenberg Skull. Pleistocene Coalition News. vol 1:2. Nov-Dec. 2009. pp.4.
 Reichelt Hugo, (1899). Diatomeen aus dem Kalktuffe aus der Gegend von Puebla in Mexiko. In: Felix, J. and Lenk, H., Eds., Beitraege zur Geologie und Palaeontologie der Republik.
 Sam VanLandingham, (2004). Corroboration of Sangamonian age of artifacts from the Valsequillo region, Puebla, Mexico by means of diatom biostratigraphy.
Micropaleontology; December 2004; v. 50; no. 4; p. 313-342; DOI: 10.2113/50.4.313
 Ibid; (2009). Extraordinary Examples of Deception in Peer Reviewing: Concoction of the Dorenberg Skull Hoax and Related Misconduct. Paper in 13th World Multi-Conference? on Systemics, Cybernetics and Informatics: International Symposium on Peer Reviewing. Orlando, Florida.
Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia2011 International Year of Forests Copyright 2009-2011 by Austin Whittall ©