![]() The cobalt vases are all modern, from Save on Crafts, and sadly discontinued. I pulled out cobalt accessories to add to the visual bounty, including this little bird open salt. The clear wine glass is an antique wheel-cut from an unknown manufacturer. Larger pieces, such as platters or punch bowls, would be obtained with coupons or proofs of sale from multiple purchases. Sturdier than “elegant” Depression glass, patterns such as this one were given away in packages of Quaker Oats or laundry detergent or by gas stations and movie theatres during the 1930s as inducements to purchasers of qualifying merchandise to part with their scarce resources. The Depression Glass tumblers, soup cups and saucers are Cobalt Royal Lace by Hazel-Atlas. We finished up with Lemon Chiffon cake garnished with fresh berries and whipped cream.īlue and white is a refreshing palette for summer the cool tones providing some visual relief from the sultry weather. The weather cooperated, and we could dine outside on Creamy Corn Crab Bisque, followed by Florentine Bistecca and Roasted Vegetables (recipe in Entertablement-Much Depends on Dinner). We took every opportunity during their short stay to get together for a Cape-Cod land-locked reprisal-Maura hosted dinner one night, Glenn and I another night, and we had dinner out twice. Its rich blue colour is also known as Sèvres blue and Thénard blue.Our good friends Bill, Maura, Carolyn and Paul, with whom we went on the cruise in 2019 (a lifetime ago, it seems), were visiting recently. Today, cobalt is still used to colour porcelain, pottery, glass, tiles and enamel jewellery. Synthetic gems dating from 1400 BC have been found at Nippur, the religious centre of the Sumerians, and these too were coloured with cobalt and cobalt glass has also been recovered from a shipwreck of around this time.Ĭobalt blue was known in China long before 1400 BC when it was used for pottery glazes, but it was always a rare pigment because cobalt minerals were scarce. Colourful historyĪmong the treasures discovered in the tomb of Pharaoh Tutankhamen, who ruled Egypt from 1361-1352 BC, was a small glass object that was coloured deep blue with cobalt. Irradiating diamonds with cobalt-60 colours them blue. This isotope, made by bombarding cobalt-59 with neutrons in a nuclear reactor, emits intense gamma-radiation and is used in medical treatment and also to irradiate food and sterilise medical supplies. Then it was a pollutant to avoid, with a half-life of 5.27 years but now we have a use for it. In the years after the second world war, when nuclear weapons were tested above ground, cobalt-60 contaminated the planet. ![]() The daily requirement of vitamin B 12 is only around 2 micrograms and the average person can store 1-2 milligrams of B 12 in their body - enough to last for more than a year. ![]() We get ours partly from food - sardines, salmon, liver, and eggs are good sources - and partly from the bacteria in our gut. Most animal species can make vitamin B 12, but not humans. Lack of this B 12 causes pernicious anaemia - the body cannot produce enough red blood cells to transport all the oxygen that it needs. ![]() For the bodyĬobalt is at the heart of vitamin B 12 where it is directly bonded to a methyl group one of the rare examples of a metal-to-carbon bond in nature. ![]() Cobalt catalysts are used in the chemical industry to convert syngas, a mixture of carbon monoxide and hydrogen, into liquid fuels. Alnico, an alloy of mainly of aluminium, nickel and cobalt, is used for permanent magnets that are very powerful although in small appliances neodymium-based magnets are now mainly used. However, it has the advantage of maintaining its magnetism to much higher temperatures iron demagnetises at 770☌ whereas cobalt's Curie point is at 1130☌. Some cobalt alloys are used in artificial body parts such as knee replacements and in dentistry.Ĭobalt can be magnetised, like iron, although it is less powerful. One alloy of cobalt, chromium, and tungsten is known as Stellite and is used for heavy duty high temperature cutting tools. Certain types of stainless steel contain it, including that used to make razor blades. Today cobalt comes mainly as a by-product of nickel production, and it is used in alloys for magnets, in ceramics, in catalysts and in paints. In 1730, the Swedish chemist Georg Brandt (1694-1768) began to investigate a similar ore found in a copper mine at Vestmanland and showed it was a hitherto unknown metal which he christened cobalt. They referred to the ore by the German name for these evil spirits, kobald (it was in fact smaltite, CoAs 2) and kobald eventually gave rise to the name of the metal itself. When, in the 1500s, silver miners in Saxony tried to smelt what they believed was a silver-bearing ore they were disappointed and cursed the mineral, saying it had been bewitched by goblins. Curiously, this element got its name by being cursed. ![]()
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