Rare Mother Coin 母錢 Guang Xu Tong Bao Beijing board Works Mint! 1875 AD

Rare Mother Coin 母錢 Guang Xu Tong Bao Beijing board Works Mint! 1875 AD

ANCIENT CHINA
Qing Dynasty
The Guangxu Emperor 1875 AD

Mother coin, 母錢





Authenticity guaranteed for all items!

Reference: Hartill: 22.1306
Obv: Guang Xu Tong Bao
Rev: Manchurian inscription " Bao Yuan "
Beijing Board of Works Mint !

Weight: 3 grams; Size: 21 mm; Material: Fine brass

 

 

揗other Coins 母錢?in old Chinese coin making

During the Han Dynasty, Chinese mints partially solved the inconsistencies in cast coins by using bronze master moulds. Master moulds were used to prepare the clay moulds which will be used for the actual casting.

Advances in the casting process in the sixth century resulted in the introduction mother coins (mu qian). Mother coins were used to impress the designs of the coin on very fine wet sand that would act as moulds for the coins. A mother coin was prepared by carefully engraving a pattern of the coin in a material that can be easily worked with such as tin.

The coin casting process involves the use of a rectangular frame filled with fine wet sand, presumably mixed with clay, and sprinkled with charcoal or coal dust. The dust allows the molten metal to flow smoothly. It also acts as a layer that separates the two halves of the moulds.

Mother coins are pressed on the wet sand in the wooden frame (first half of the mould). Rods are placed between the coins to create channels where the molten metal can flow. A second frame (second half of the mould) is placed on top and pressed tightly. This imprints the designs of the obverse and reverse of the mother coins on the sand in the frames.

The mother coins are then removed and transferred on top of the second frame to create new moulds. This processed is repeated until up to fifteen layers of moulds are created. The wooden frames are bound tautly and filled with molten metal, usually bronze.

This process creates a 揷oin tree,?cast coins connected by hardened metal on the channels. After brushing off the sand, coins are broken of the 搕ree.?

To make the edges smooth, the coins are strung together on a long square rod and the coin edges are filed down. It is further polished in tubs of chaff or sand before the final stringing.
The use of mother coins proved to be effective in controlling the quality of the coins. Slight differences between mother coins still existed however skillful the carver is.

 

 

 

Shipping policy:
Economy Regular mail shipping: 3.99 Euro worldwide (buyer's risk for lost by post!)

If the total value is above 50 Euro, Registered mail is required for safety reasons.
Registered mail shipping:
11.99 Euro within Europe, 16.99 Euro worldwide, Combined shipping accepted.

Rare Mother Coin 母錢 Guang Xu Tong Bao Beijing board Works Mint! 1875 AD

$49.00Price