Get the best deals on Japan 10 Sen Coin when you shop the largest online selection at 4insure.us Free shipping on many items | Browse. Sentient Coin Price Chart | Market Capitalization | SEN to USD Calculator | SEN ROI Calculator | News | Description | Team | Related Events | Community. Nickel coin: 5 sen. Copper coins: 1 sen Nickel coin: Nickel, 25 per cent ; copper, 75 per cent. No. 4. Copper 50 - sen silver coin, grams. No. 5. Overall, the aluminum coin was more successful than its brass counterpart, having sen coin used until due to being made of a more inexpensive and less demanded metal. It had a mass of 3. Once again, to lower costs and to save other resources for weaponry, the coin was composed of aluminum. This new design features the paulownia coat of armsis On this coin's obverse was the Imperial Seal with the value, with two branches at the side. It was composed of tin-zincdue to the need sen coin other metals for fighting in World War II, just like the use of aluminum in some coins before sen coin.