Coins of the Indian rupee 3, 5, 10, 20, 25, 50 (naya) paisa and one rupee. Since rupees retained their pre-decimal value, pre-decimal coins of one, half and quarter rupees remained in circulation after decimalisation. The word "naya" was dropped in 1964 and a new denomination, the 3 paisa, was introduced into circulation. A 20 paisa coin was minted in 1968. Neither of these coins gained much popularity. The 1, 2 and 3 paisa coins were phased out gradually in the 1970s. In 1982, a new 2 rupee coin was introduced experimentally to replace 2 rupee notes. The 2 rupee coin was not minted again
Decimal separator In the Middle Ages, before printing, a bar ( ¯ ) over the units digit was used to separate the integral part of a number from its fractional part, e.g. 995 (meaning, 99.95 in decimal point format). This practice derived from the decimal system used in Indian mathematics and was popularized by the Persian mathematician Al-Khwarizmi, when Latin translation of his work on the Indian numerals introduced the decimal positional number system to the Western world. His "Compendious Book on Calculation by Completion and Balancing" presented the first systematic solution of linear and quadratic equations in Arabic. A similar notation