Younger Dryas also known as Dryas III was a mini Ice Age that lasted from around 10,700 BC until around 9600 BC. It is named after a flower that flourished during this relatively short period. In Ireland the period is known as the Nahanagan Stadial and in Britain as the Loch Lomond Stadial. For about thirteen hundred years the glaciers had been slowly retreating until within a short time-span temperatures dropped and they began to advance again. The cause of this cooling is not absolutely clear. One view is that a sudden release into the North Atlantic of vast quantities of fresh water that had been contained by huge ice dams is assumed to have closed down the Gulf Stream, resulting in a twelve hundred year lowering of global temperatures. There is evidence that the change only took one or two decades. The same threat is said to exist today with the possibility of the melting of the Greenland ice cap.
The most recent theory, by Firestone, West and Warwick-Smith, links the onset of the Younger Dryas with the explosion of a comet over North America that led to the extinction of many species, the collapse of the Clovis culture(a)(b) as well as the creation of the Carolina Bays.
A 2014 paper(g) entitled Nanodiamond-Rich Layer Across Three Continents Consistent with Major Cosmic Impact at 12,800 Cal BP by Charles R. Kinzie et al., has developed further the idea of this event being associated with the Younger Dryas. In a similar vein is an article(h) from Megan Gannon.
A recent application of archaeoastronomy by Martin Sweatman and Dimitrios Tsikritsis led them to conclude that the carved symbols at Göbekli Tepe recorded an encounter involving the explosion or impact of part of Encke’s Comet around 13,000 years ago, which triggered the Younger Dryas Event that provided the impetus for the Neolithic Revolution. Sweatman later expanded their work in his book Prehistory Decoded  and in an article on the Ancient Origins website(m).
Kevin A. & Patrick J. Casey maintain that a globally catastrophic event occurred 13,000 years ago(l). The kernel of their theory is that originally the Earth had two moons that at some later point collided, producing our current Moon, while the remnant of the second one eventually exploded over North America kick-starting what we refer to as the cooler Younger Dryas period. They are adamant that it was not a comet or asteroid that caused the devastation, and so clash with the work of Richard Firestone and his colleagues.
In 2015 a paper constraining the impact date to within 100 years using Bayesian statistical analyses, now proposed as 12,835 -12,735 years ago(j).
Coincidentally, Professor Emilio Spedicato independently arrived at the conclusion that it was a cometary impact in the North Atlantic that was responsible for the Younger Dryas. Subsequently, when temperatures rose again it resulted in the flooding of vast areas of low-lying landmasses that in Spedicato’s opinion, included Atlantis, which he locates in Hispaniola.
Conflicting evidence regarding the possibility of the Younger Dryas being caused by such an impact is impartially outlined on the internet(c).
December 2014 saw Graham Hancock raising the issue of a cometary cause for the Younger Dryas and its possible association with ancient Egypt(f).
The November 2013 issue of the BBC Focus magazine (p.30) had a brief article on the impact theory, noting that the northern hemisphere saw a drop of as much as 15°C around 11,000BC. In the absence of a suitable impact crater there is still much scientific scepticism(d).
However in early 2017, further possible evidence of an impact at the start of the Younger Dryas was offered by a team led by Christopher Moore of the University of South Carolina, when they identified a distinct layer of platinum in the soil that coincided with the start of YD. Commenting on this anomaly Moore noted that “Platinum is very rare in the Earth’s crust, but it is common in asteroids and comets.”(i)
In early 2018, two papers were published online(k), reinforcing the YD impact theory and adding evidence that the event resulted in a conflagration that “may have consumed – 10 million km2, or – 9% of Earth’s terrestrial biomass”.*Related to this is a paper by Andrew Collins that draws attention to the ‘Usselo horizon’, a charcoal-rich layer of between 1 and 8 inches, found on all continents, indicating widespread fires, now dated to 12,900 years ago(n).*
Ice cores from Greenland indicate a further cooling period circa 6200 BC that may be related to the abandonment of many Neolithic settlements during this period. Other periods of abrupt climate change have been identified from 3800 BC to 3500 BC and 2800 BC to 2000 BC.
The fact that Plato’s apparent date for the demise of Atlantis, circa 9600 BC, roughly corresponds with the current, best estimate for the date of the Younger Dryas is interesting but unfortunately not conclusive proof of any direct connection. In the absence of any supportive archaeological evidence, a linkage between Atlantis and the Younger Dryas will have to remain a matter of faith rather than fact. Interesting but inconclusive.
Recent discoveries in northern Sudan of dozens of skeletons, the majority of whom were apparently killed by flint-tipped arrows, have led to the suggestion(e) they were the result of food shortages resulting from the Younger Dryas that in turn led to warfare over diminished food availability.
(c) http://blogs.nicholas.duke.edu/thegreengrok/climatedebate/ (offline Dec. 2016) See: https://web.archive.org/web/20130310032309/http://blogs.nicholas.duke.edu/thegreengrok/climatedebate/
Orichalcum is one of the many mysteries in Plato’s Atlantis narrative. It is mentioned five times in the Critias [114e, 116c-d, 119c] as a metal extensively used in Atlantis. I am not aware of any reference to it anywhere else in his writings, a fact that can be advanced as evidence of the veracity of his Atlantis story. Plato took the time to explain to his audience why the kings of Atlantis have Hellenised names. However, he introduces Orichalcum into the story without explanation suggesting that the metal was something known to the listeners. It is therefore natural to expect that metals might play an important part in determining the credibility of any proposed Atlantis location.
*Bronze was an alloy of copper and tin, while brass was a mixture of copper and zinc, their similarity is such that museums today refer to artefacts made of either refer to them as copper alloys.*
According to James Bramwell[195.91], Albert Rivaud demonstrated that the term ‘orichalcum’ was known before Plato and not just invented by him. Similarly, Zhirov notes that both Homer and Hesiod refer to the metal[0458.46], , as does Ibycus, the 6th century BC poet, who compares its appearance to gold suggesting a brasslike alloy. Thomas Taylor (1825) noted that in a fragment from a lost book of Proclus, he seems to refer to orichalcum under the name of migma(c). Wikipedia also adds that “Orichalcum is also mentioned in the Antiquities of the Jews – Book VIII, sect. 88 by Josephus, who stated that the vessels in the Temple of Solomon were made of orichalcum (or a bronze that was like gold in beauty). Pliny the Elder points out that the metal had lost currency due to the mines being exhausted. Pseudo-Aristotle in ‘De mirabilibus auscultationibus’ describes orichalcum as a shining metal obtained during the smelting of copper with the addition of ‘calmia’, a kind of earth formerly found on the shores of the Black Sea, which is attributed to be zinc oxide.”
Orichalcum, or its equivalent Latin Aurichalcum, is usually translated as ‘golden copper’ referring to either its colour or composition (80% copper and 20% zinc) or both. However, Webster’s Dictionary translates it as ‘mountain-copper’ from ‘oros’ meaning mountain and ‘chalchos’ meaning copper.
Sir Desmond Lee described the metal as ‘imaginary’ without explaining away the classical references or the fact that ”In numismatics, orichalcum is the name given to a brass-like alloy of copper and zinc used for the Roman sestertius and dupondius. Very similar in composition to modern brass, it had a golden-yellow color when freshly struck. In coinage, orichalcum’s value was nearly double reddish copper or bronze. Because production cost was similar to copper or bronze, orichalcum’s formulation and production were highly profitable government secrets.”(m)
Modern writers have offered a range of conflicting explanations for both the origin and nature of orichalcum. A sober overview of the subject is provided by the Coin and Bullion Pages website(d).
In 1926 Paul Borchardt recounted Berber traditions that recalled a lost City of Brass. Salah Salim Ali, the Iraqi scholar, points out that a number of medieval Arabic writers referred to an ancient ‘City of Brass’ echoing the Orichalcum covered walls of Plato’s Atlantis.
Ivan Tournier, a regular contributor to the French journal Atlantis proposed that orichalcum was composed of copper and beryllium. Tournier’s conclusion seems to have been influenced by the discovery in 1936 at Assuit in Egypt of a type of scalpel made from such an alloy(e).
An unusual suggestion was made by Michael Hübner who noted that “small pieces of a reddish lime plaster with an addition of mica were discovered close to a rampart” in his chosen Atlantis location of South Morocco. He links this with Plato’s orichalcum, but does so without any great enthusiasm.
Jim Allen, promoter of the Atlantis in Bolivia theory, claims that a natural alloy of gold and copper is unique to the Andes. Tumbaga is the name given by the Spaniards to a non-specific alloy of gold and copper found in South America. However, an alloy of the two that has 15-40% copper, melts at 200 Co degrees less than gold. Dr. Karen Olsen Bruhns, an archaeologist at San Francisco State University wrote in her book, Ancient South America, “Copper and copper alloy objects were routinely gilded or silvered, the original colour apparently not being much valued. The gilded copper objects were often made of an alloy, which came to be very important in all of South and Central American metallurgy: tumbaga. This is a gold-copper alloy which is significantly harder than copper, but which retains its flexibility when hammered. It is thus ideally suited to the formation of elaborate objects made of hammered sheet metal. In addition, it casts well and melts at a lower temperature than copper, always a consideration when fuel sources for a draught were the wind and men’s lungs. The alloy could be made to look like pure gold by treatment of the finished face with an acid solution to dissolve the copper, and then by hammering or polishing to join the gold, giving a uniformly gold surface”.
Enrico Mattievich also believed that orichalcum had been mined in the Peruvian Andes(b).
Jürgen Spanuth tried to equate Orichalch with amber. Paul Dunbavin links Orichalcum with Wales. Robert Ishoy implies a connection between obsidian and Orichalcum, an idea also promoted by Christian & Siegfried Schoppe, while Felice Vinci equates it with platinum.
Albert Slosman thought that there was a connection between Moroccan oricalcita, a copper derivative, and Plato’s orichalcum. Peter Daughtrey has offered [893.82] a solution from a little further north in Portugal where the ancient Kunii people of the region used ori or oro as the word for gold and at that period used calcos for copper.
Thorwald C. Franke has suggested[750.174] that two sulphur compounds, realgar and orpiment whose fiery and sometimes translucent appearance might have been Plato’s orichalcum. His chosen location for Atlantis, Sicily, is a leading source of sulphur and some of its compounds. I doubt this explanation as realgar disintegrates with prolonged exposure to sunlight while it and orpiment, a toxin, could not be described as metals comparable with gold and silver as stated by Plato.
Frank Joseph translates orichalcum as ‘gleaming or superior copper’ rather than the more correct ‘mountain copper’ and then links Plato’s metal with the ancient copper mines of the Upper Great Lakes. Joseph follows Egerton Sykes in associating ‘findrine’, a metal referred to in old Irish epics, with orichalcum. However, findrine was usually described as white bronze unlike the reddish hue of orichalcum.
Ulf Erlingsson suggested [319.61] that orichalcum was ochre, which is normally yellow, but red when burnt. He seems to have based this on his translation of the text Critias116b. In fact the passage describes the citadel flashing in a fiery manner, but it does not specify a colour!
Other writers have suggested that orichalcum was bronze, an idea that conflicts with a 9600 BC date for the destruction of Atlantis since the archaeological evidence indicates the earliest use of bronze was around 6000 years later.
Thérêse Ghembaza has kindly drawn my attention to two quotations from Pliny the Elder and Ovid that offer possible explanations for Plato’s orichalcum (see Document 091011). The former refers to a Cypriot copper mixed with gold which gave a fiery colour and called pyropus, while Ovid also refers to a cladding of pyropus. She also mentions auricupride(Cu3Au), an alloy that may be connected with orichalcum.
Zatoz Nondik, a German researcher, has written a book about Plato’s ‘orichalcum’, From 2012 to Oreichalkos, in which he describes, in detail, how the orichalcum may be related to Japanese lacquer and suitable for coating walls as described in the Atlantis(b) narrative!
The fact is that copper and gold mixtures, both natural and manmade, have been found in various parts of the world and have been eagerly seized upon as support for different Atlantis location theories. A third of all gold is produced as a by-product of copper, lead, and zinc production.
It is also recorded that on ancient Crete, in the Aegean, two types of gold were found, one of which was a deep red developed by the addition of copper. Don Ingram suggests that the reddish gold produced in ancient Ireland is what Plato was referring to.
Irrespective of what orichalcum actually was, I think it is obvious that it was more appropriate to the Bronze Age than 9,600 BC. Furthermore, it occurs to me that Plato, who was so careful to explain or Hellenise foreign words so as not to confuse his Athenian audience, appears to assume that orichalcum is not an alien term to his audience.
The result of all of this is that Orichalcum has been advanced to support the location of Atlantis in North and South America, Sundaland, Ireland, Britain and the Aegean. Once again an unintentional lack of clarity in Plato’s text hampers a clear-cut identification of the location of Atlantis.
A fascinating anecdote relating the use of a term similar to ‘orichalcum’ to describe a mixture of copper and gold was used by a metalsmith in Dubai as recently as 2007 and is recounted on the Internet(a) .
The Wikipedia entry(f) for ‘orichalcum’ adds further classical references to this mysterious metal.
2015 began with a report that 47 ingots of ‘orichalcum’ had been found in a shipwreck off the coast of Sicily and dated to around 600 BC(g). What I cannot understand is that since we never knew the exact composition of Plato’s alloy, how can anyone today determine that these recovered ingots are the same metal. Thorwald C. Franke has more scholarly comments on offer(h). Jason Colavito has also applied his debunking talents to the subject(i). In June of the same year, Christos Djonis, in an article(j) on the Ancient Origins website, wrote a sober review of the media coverage of the shipwreck. He also added some interesting background history on the origin of the word ‘orichalcum’.
An analysis revealed(k) that those ingots were composed of 75-80% copper, 15-20% zinc, and traces of nickel, lead and iron, but no proof that this particular alloy was orichalcum. The recovery of a further 39 ingots from the wreck were reported in February 2017 and the excavation of the sunken ship continues.
The most recent explanation for the term comes from Dhani Irwanto who has proposed that orichalcum refers to a form zircon(l) that is plentiful on the Indonesian island of Kilimantan, where he has hypothesised that the Plain of Atlantis was located [1093.110].
(e) Atlantis Research Vol 2. No.6, Feb/Mar 1950, p.86
*(g) http://news.discovery.com/history/archaeology/atlantis-legendary-metal-found-in-shipwreck-150106.htm (link broken Oct. 2018) See: Archive 2460*