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Folded edge
Folded edge The folded edge is a type of coin error caused by a marginal break along the edge of one of the blanking punches installed on the punching press. During the shearing of the planchet, the broken punch generates a metal tab on the edge, which is then flattened inward over the surface of…
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Cutting errors – Clips
Cutting errors – Clips Elliptical clip Cutting errors, specifically clips, are a type of coin error that occur when a portion of the planchet is accidentally cut out during the production process. This error can happen during the blanking process, when a circular disk is cut from the metal strip that will become the planchet.…
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Alloy errors
Alloy errors It is common for coins to have imperfections in the composition of the metal alloy, although extreme cases are less frequent. These variations in the alloy’s composition can arise during the casting process in the foundry.To obtain planchets that comply with the issue decree, it is essential to dose the different metals that…
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Unstruck planchet
Unstruck planchet An unstruck planchet is a blank coin that has not been struck by a die, resulting in a coin that has no design or markings. This type of error can occur during the manufacturing process when a planchet is not properly fed into the coin press or when a planchet is not struck…
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How to Help Breeding Birds
How to help breeding birdsBird breeding season is a critical time for our feathered friends, as they work tirelessly to raise the next generation. During this period, birds require extra support and protection to ensure their survival and success. For bird lovers, this is an opportunity to take action and contribute to the conservation of…
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How to Help Birds Migrate
How to Help Birds Migrate Provide Food and Water Enhance Window Visibility Turn Off the Lights Support Conservation Efforts Bird migration is an impressive feat where birds can navigate over long distances without modern technology. However, they are facing challenges such as habitat loss and climate change. As individuals, there are several ways we can…
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The Bird’s Guide to Molt Season
The Bird’s Guide to Molt Season It can seem strangely quiet with fewer birds and no bird songs to be heard in the garden. The birds that do appear can look disheveled. Don’t worry! They are just in molting season. How often do birds moult? Most birds will go through this process once or twice…
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Topaz
Price Retail price for 1 carat plus topaz:Quality from high to lowLondon blue: $15-$25/ctSwiss blue: $8-$20/ctSky blue: $3-$20/ctColorless: $3-$26/ct Main origin The main origins of topaz are Brazil, Russia, Sri Lanka, Afghanistan, Pakistan, and the United States. Brazil’s state of Minas Gerais is the world’s most important source of precious topaz, which is mostly cut…
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Tanzanite
Tanzanite Price Retail price for top color tanzanite:Carat size from large to small5 carats plus: $75-$1500/ct1-3 carats: $75-$1200/ct0.5-1 carat: $75-$500/ct Main origin The Merelani Hills in northern Tanzania is the only location where commercial mining of tanzanite takes place. Imitation Coranite – synthetic blue corundum, tanavyte – purple YAG, glass Synthetic blue corundum Blue glass…
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Sapphire
Sapphire Price Retail price for 1-2 carat heated blue sapphire:Quality from high to lowTop grade: $1600-$3900/ctVery good grade: $1400-$2700/ctGood grade: $1200-$2100/ctFair grade: $275-$1125/ct Typically, mid-quality untreated blue sapphire will sell for 20-30% more than a treated stone of the same quality. Main origin The Burma (Myanmar) and Kashmir are two well-known regions that are famous for…