Science Fair Projects Ideas - Hammered coinage

All Science Fair Projects

      

Science Fair Project Encyclopedia for Schools!

  Search    Browse    Forum  Coach    Links    Editor    Help    Tell-a-Friend    Encyclopedia    Dictionary     

Science Fair Project Encyclopedia

For information on any area of science that interests you,
enter a keyword (eg. scientific method, molecule, cloud, carbohydrate etc.).
Or else, you can start by choosing any of the categories below.

Hammered coinage

Hammered coinage describes the commonest form of coins produced since the invention of coins in the first millennium BC until the early modern period of ca. the 15th-17th centuries.

Hammered coins were produced by placing a blank piece of metal (a planchet or flan) of the correct weight between two dies, and then striking the upper die with a hammer to produce the required image on both sides. The bottom die (sometimes called the anvil die) was usually counter sunk in a log or other sturdy surface and was called a pile. (This is probably related to the modern term pile driver.) One of the minters held the die for the other side, called the trussel, in his hand while it was struck either by himself or an assistant.

In later history, in order to increase the production of coins, hammered coins were sometimes produced from strips of metal of the correct thickness, from which the coins were subsequently cut out. Both methods of producing hammered coins meant that it was difficult to produce coins of a regular diameter, and coins were liable to suffer from "clipping" where unscrupulous people would remove slivers of precious metal since it was difficult to determine the correct diameter of the coin, or "sweating" when silver coins would be placed in a bag which would be vigorously shaken so that silver dust would be produced which could later be removed from the bag.

In England the first non-hammered coins were produced in the reign of Queen Elizabeth I in the 1560s, but while machine-produced coins were experimentally produced at intervals over the next century, the production of hammered coins did not finally end until 1662.

An alternative method of producing early coins, particularly found in Asia, especially in China, was to cast coins using moulds. This method of coin production continued in China into the nineteenth century. Up to a couple of dozen coins could be produced at one time from a single mould, when a 'tree' of coins (which often contained features such as a square hole in the centre) would be produced and the individual coins (called cash) would then be broken off.

03-10-2013 05:06:04
The contents of this article is licensed from www.wikipedia.org under the GNU Free Documentation License. Click here to see the transparent copy and copyright details
Science kits, science lessons, science toys, maths toys, hobby kits, science games and books - these are some of many products that can help give your kid an edge in their science fair projects, and develop a tremendous interest in the study of science. When shopping for a science kit or other supplies, make sure that you carefully review the features and quality of the products. Compare prices by going to several online stores. Read product reviews online or refer to magazines.

Start by looking for your science kit review or science toy review. Compare prices but remember, Price $ is not everything. Quality does matter.
Science Fair Coach
What do science fair judges look out for?
ScienceHound
Science Fair Projects for students of all ages
All Science Fair Projects.com Site
All Science Fair Projects Homepage
Search | Browse | Links | From-our-Editor | Books | Help | Contact | Privacy | Disclaimer | Copyright Notice