Egyptian Blue – The Oldest Known Artificial Pigment
Egyptian Blue, also known as calcium copper silicate, is one of the first artificial pigments known to have been used by man. The oldest known example of the exquisite pigment is said to be about 5000 years old, found in a tomb painting dated to the reign of Ka-Sen, the last pharaoh of the First Dynasty. Others, however, state that the earliest evidence of the use of Egyptian blue is from the Fourth Dynasty and the Middle Kingdom, around 4,500 years ago. Nevertheless, by the New Kingdom, Egyptian Blue was used plentifully as a pigment in painting and can be found on statues, tomb paintings and sarcophagi. In addition, Egyptian blue was used to produce a ceramic glaze known as Egyptian faience.
Egyptian faience hippopotamus. Credit: British Museum
Its characteristic blue colour, resulting from one of its main components — copper — ranges from a light to a dark hue, depending on differential processing and composition. If the pigment is ground coarsely, it produces a rich, dark blue, while very finely-ground pigment produces a pale, ethereal blue. It is made by heating a mixture of a calcium compound (typically calcium carbonate), a copper-containing compound (metal filings or malachite), silica sand and soda or potash as a flux, to around 850-950 C.
In Egyptian belief, blue was considered as the colour of the heavens, and hence the universe. It was also associated with water and the Nile. Thus, blue was the colour of life, fertility and rebirth. One of the naturally blue objects that the Egyptians had access to was lapis lazuli, a deep blue semi-precious stone which could be ground up into powder, although this was a luxury item and had to be imported from Afghanistan. Therefore, it is not too surprising that the Egyptians sought to produce a synthetic pigment to use as a substitute for the blue lapis lazuli.
Hunting in the marshes (fragment), tomb chapel of Nebamun. Credit: British Museum.
The manufacture of Egyptian Blue eventually spread beyond Egypt’s borders, and can be found throughout the Mediterranean. Egyptian Blue has been found in numerous Greek and Roman objects, including statues from the Parthenon in Athens and wall paintings in Pompeii. Despite its extensive application in art, Egyptian Blue ceased to be used, and its method of production was forgotten when the Roman era came to an end.
In the 19th century, Egyptian Blue was re-discovered. The excavations at Pompeii revealed that many wall paintings had Egyptian Blue on them, and this prompted scientists to investigate the exact composition of this pigment. Since then, researchers have gained a much deeper understanding of its unique properties. Experiments found that Egyptian Blue has the highly unusual quality of emitting infrared light when red light is shone onto it. This emission is extraordinarily powerful and long-lived, but cannot be seen by the naked eye, because human vision does not normally extend into the infrared range of the light spectrum. In addition, scientists unexpectedly discovered that Egyptian Blue will split into ‘nanosheets’ – a thousand times thinner than a human hair – if stirred in warm water for several days. Scientists now believe that its unique properties may make Egyptian Blue suitable for a variety of modern applications.
Egyptian Blue may one day be utilized for communication purposes, as its beams are similar to those used in remote controls and telecommunication devices. Moreover, Egyptian blue could be used in advanced biomedical imaging, as its near-infrared radiation is able to penetrate through tissue better than other wavelengths. As an ink solution, Egyptian blue opens up new ways for its incorporation into modern appliances, such as the development of new types of security ink and possibly as a dye in the biomedical field. While the use of Egyptian blue in modern high-tech applications is still in its infancy at this stage, it does seem that its future is a bright one.
I’m going on holiday next week. I thought I’d print my boarding pass off at lunch today, I couldn’t find it on the default printer and I was so confused… then I remembered where I’d printed to last and just about died when I saw the results…
so this morning i was playing with the slow-mo mode on my phone, hoping to get a majestic vid of a bumblebee taking off
but instead i found this dumbfuck
This was my interview with the Executive Producers from Constantine. I asked a question to David S Goyer regarding the rumors on Constantine and the bisexual erasure that has been floating around the internet.
I tried to keep my question respectful, as I’m a junior journalist, and didn’t want to rock the boat. …getting accused of being a fake geek girl, being told that because he wasn’t bisexual until 12 years into the comics it doesn’t really matter….was not what I expected. The guy picked a fight with me, and as someone who genuinely has loved his screen writing work, I was really disappointed.
I understand that he may be defensive, given the amount of questions he’s been getting on the subject recently, but speaking to me like this wasn’t…called for?
I will say the other producer, Daniel Cerone, was very nice and gracious, as was the entirety of the cast. I can only hope that Mr. Goyer was just running on little sleep.
But still, some of my followers wanted me to ask the question, and I did. Here is your answer. (Also I know I should have said Vertigo, not Image—that I got some of my facts wrong, but I was a bit flustered, so I think I can be forgiven the mistake).
I think the absolute worst part of this is the fact that both of them (meaning the producers, not Mr. Goyer and the interviewer) seem to be implying that the only way to explicitly acknowledge his bisexuality onscreen is to have him sleep with a man. That and the fact that he is basically saying over and over again that bisexuality is just unimportant (and yes, that really is the implication of “it’s unimportant to the character” it really really is.) Apparently being a smoker has waaaaay more affect on what kind of person someone is. That’s new information to me.
I won’t be watching this show and I honestly just utterly loathe this bigoted sack of shit who is reponsible for it
Any clueless fucking moron who thinks that a characters sexuality is ‘unimportant’ is the kind of cretin whose work I am not going to have ANY interest or desire to support with either my time or my money
Honestly seeing this bullshit from David S Goyer doesn’t surprise me in the least. I don’t know whether he’s got a problem with bisexuals or whether he’s just being a good boy and doing what the network tells him because their too fucking cowardly, WEAK and SPINELESS to have an openly bisexual hero starring in their show and he’s too pathetic to insist upon it…nor do I care. I loathe COWARDS as much as I despise bigots
Either way, I’m not wasting one second of my time on watching Constantine
You know why he wasn’t shown as bi until 12 years into the comic? BECAUSE THE CHARACTER WAS INTRODUCED IN 1985!! Are they seriously advancing the argument that his bisexuality isn’t important because it wasn’t part of the original story — which was written during the height of panic and misinformation about AIDS, in which gay and bisexual men were regularly demonized in media with virulent homophobia?
It isn’t 1985 any more and these excuses just don’t cut it. Especially not when delivered with a smug grin like David S. Goyer is excited to have a ‘gotcha!’. The cultural climate today is VASTLY different then in 1985. I don’t think he realizes how awful that makes him and his show look that they are building excuses around what was a really dark time for the queer community.
Also I’m not sure I understand what Daniel Cerone is saying about making the story darker and the lack of interference from NBC. It doesn’t really help their case. Is he arguing that no one at NBC told them to strip the bi from John Constantine? Because then it sounds like the change is just coming from their personal prejudices against bi men. There are more ways to show a character is bi then to have him jump in bed with a dude. Seriously. Your excuse is ‘it’s not network pressure we’re just lazy writers’?
David Goyer is canon a massive tool.
Also, they suck at math. Hellblazer #51 was March 1992. That’s seven years, not 12 (and it took me 21 to come out so they can kiss my heiney. Like no one’s ever stayed in the closet a while).
Ok, I’m not that into comics and I’m getting my information from wikipedia so fair warning there, but there was a ban on depicting homosexual characters until 1989. The ban on referring to homosexuality was revised in 1989 to allow non-stereotypical depictions of gays and lesbians.
Constantine came out of the closet when he was ALLOWED to come out of the closet.
While the Comics Code Authority rules regarding homosexual characters impacted the possibility of outing mainstream characters for years and years, even before Vertigo Hellblazer was a mature readers title and was not subject to the CCA (nor were its contemporaries pre-Vertigo: Swamp Thing and Sandman). Were John Constantine ever constrained by the CCA he would have been a vastly different character in many other ways as well. Whatever reason they took 7 years to out him, the ban wasn’t likely the cause.
There’s two types of anger one is dry and the other wet and basically wet anger is when your eyes water and your voice shakes and I hate that cause I feel weak when I’m crying while angry I like dry anger when your face is like stone and your voice is sharp I guess wet anger shows that you care too much and dry anger means you’re done.
This is the best description ever