The basic consideration to be met in the attribution of a coin is the determination of denomination. Since denominations are usually expressed in numeric rather than word form on a coin, this is usually quite easily accomplished on coins from nations which use Western numerals, except in those instances where issues are devoid of any mention of face value, and denomination must be attributed by size, metallic composition or weight.
The sphere of countries stretching from North Africa through the Orient, on which numeric symbols generally unfamiliar to Westerners are employed, often provide the collector with a much greater challenge. This is particularly true on nearly all pre-20th Century issues. On some of the more modern issues and increasingly so as the years progress, Western-style numerals usually presented in combination with the local numeric system are becoming more commonplace on these coins.
Although denomination numerals are generally prominently displayed on coins, it must be remembered that these are general representations of characters, which individual coin engravers may have rendered in widely varying styles. Where numeric or script denominations designation forms peculiar to a given coin or country apply, such as the script used on some Persian (Iranian) issues.