The silver piece, or sp for short, is an integral part of the default monetary system in the D&D system since its inception. All prices in the core rulebooks and boxed sets are given primarily in gold pieces (gp), with items of lesser value given in silver pieces (sp) or copper pieces (cp), which are monetary fractions of the standard gp.
While the gp is the most common coin used by adventurers, most economies in fantasy settings actually have the silver piece as their foundations, with most wages calculated in silver pieces, not gold.
Size and Weight
The silver piece is generally considered to be a coin, though ingots or trade bars made of silver or other materials may be worth multiple silver pieces or even fractions thereof. In coin form, it is generally described as “approximately the size and weight of a United States half-dollar coin” meaning 30.6mm in diameter and weighing 11.5 grams (approximately 40 to a pound). Pre-1965 US half dollar coins are made of 90% silver, 10% copper, which is a very reasonably accurate representation of the composition of good quality medieval European silver coins.
In “Basic” D&D (and previous editions) and First Edition AD&D, despite the described weight, silver pieces are considered to weigh a tenth of a pound (1.6 standard ounces) each for encumbrance purposes, with 10 sp weighing one pound. Indeed, in these editions of the game, the basic unit of weight/encumbrance is either the “coin” (cn in Basic D&D) or the “Gold Piece Weight” (gpw), either of which equals one tenth of a pound.
Starting in Second Edition AD&D and continuing through Third and Fourth Editions, silver pieces are considered to weigh approximately a third of a standard ounce (9 grams) each, which equals about fifty gp to a pound, while maintaining the size consistent with previous editions.
As part of the default monetary system of all editions and versions of D&D, the sp is a staple in the system, but its relative value varies depending on edition.
1979 3rd Edition:
- 1 gp = 10 sp = 50 cp = 2 ep = 1/5 pp (meaning 5 gp = 1 Platinum Piece) 
- Note that 1 sp = 5 cp; in all other editions, 1 sp = 10 cp
1981 4th Edition:
First Edition AD&D
- 1 gp = 20 sp = 200 cp = 2 ep = 1/5 pp 
As can be seen, an attempt at replicating a real world economy was made; the 20 sp = 1 gp corresponds to the pre-decimalisation British system of 20 shillings to a Pound Sterling.
Second Edition AD&D
- 1 gp = 10 sp = 100 cp = 2 ep = 1/5 pp 
With 2e, a return to the simple decimal system was made, presumably due to the familiarization of most players with such a system.
Third Edition and Beyond
- 1 gp = 10 sp = 100 cp = 2 ep = 1/10 pp
With the introduction of the third edition (and the d20 System), the trend toward decimalization reached its logical conclusion; the platinum piece doubled in value to 10 gp (from the earlier 5 gp), so that with the exception of the electrum piece, each coin is exactly one tenth the value of the coins “above” it, i.e.: 1 pp = 10 gp = 100 sp = 1,000 cp. This continued through the Fourth Edition.
Silver coins in the real world
US Silver coins
As previously mentioned, the 90% silver pre-1965 half-dollar coins are the quintessential silver pieces. It should be noted that prior to 1965, all US coins (with the exception of the one and five cent copper and nickel coins… and the obvious gold coins) were made of silver; quarter-dollars were exactly half the weight of a half-dollar, silver dollars were exactly twice the weight of a half dollar, dimes were exactly 1/5 the weight of a half dollar and half-dimes (silver coins worth 5 cents) were exactly 10 to a half dollar in weight.
British silver coins
The quintessential silver British coin is the shilling; a 92.5% (.925) pure silver coin slightly smaller than a US quarter dollar coin. Twenty shillings made up one Pound Sterling (which does not weigh one pound), leading to the term sterling silver being used to denote .925 purity silver. Silver was minted in other denominations; the Crown was a heavy silver coin worth five shillings and was approximately the same size and weight as a US Silver Dollar. The Crown led to the creation of the Half-Crown, predictable enough, half the weight of a Crown (and very close in size and weight to the US half dollar. Other silver coins are the two-shilling Florin, the half-shilling Sixpence and the quarter-shilling Threepence.
Silver coins in different campaign settings
Silver Pieces are called Falcons in Cormyr, Tarans in Amn, Decarches in Calimport, Shards in Waterdeep, Bedoars in Cormanthyr and Dirhams in Southern Lands. Sembia mints triangular coins of the same weight called Ravens.
- ↑ Dungeons & Dragons Basic Rules pp B20 4th ed. Jan 1981 - "Moldvay red book"
- ↑ Dungeons & Dragons Basic Rules page 33 3rd ed. Dec 1979 - "Holmes blue book"
- ↑ Dungeons & Dragons Basic Rules pp B47 4th ed. Jan 1981 - "Moldvay red book"
- ↑ Advanced Dungeons & Dragons Player's Handbook pp 35 1st ed. 1978
- ↑ Advanced Dungeons & Dragons Player's Handbook pp __ 2nd ed. 1989
- ↑ SRD
See also: SRD:Wealth and Money