The gold piece, or gp for short, is the foundation 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 gp, with items of lesser value given in silver pieces (sp) or copper pieces (cp), which are monetary fractions of the standard gp.
Size and WeightEdit
The gold piece is generally considered to be a coin, though ingots or trade bars made of gold or other materials may be worth multiple gold pieces. 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 an avoirdupois pound). In “Basic” D&D (and previous editions) and First Edition AD&D, despite the described weight, gold pieces are considered to weigh a tenth of an avoirdupois pound (1.6 avoirdupois ounces) each for encumbrance purposes, with 10 gp weighing one avoirdupois 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, gold pieces are considered to weigh approximately a third of an avoirdupois ounce (9 grams) each, which equal about fifty gp to an avoirdupois pound, while maintaining the size.
It should be noted that the avoirdupois ounce and pound is different than the Troy ounce and pound (which is used for precious metals). An avoirdupois ounce is 0.9114 Troy ounce and an avoirdupois pound is 14.58 Troy ounces (1.215 Troy pounds).
As part of the default monetary system of all editions and versions of D&D, the gp is a staple of the system, but its relative value varies depending on edition.
1974 1st Edition (OD&D):
1979 3rd Edition (Holmes):
1981 4th Edition (Moldvay/Cook B/X):
First Edition AD&DEdit
- 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.
It should be mentioned that by the rules in the DMG a character was supposed to "automatically expend not less than 100 gold pieces per level of experience per month". It was even worst regarding leveling up as the cost of doing so was the "Level of the trainee character * 1,500 gp = Weekly cost during study/training" with the number of weeks being 1 to 4 depending on how good the player role played.
As expected any DM who tried to follow this rule and gave out enough wealth that his players could easily get to the next level quickly found themselves in a death spiral of having to giving out more and more treasure to "one up" the previous adventure resulting in the dreaded Monty Haul campaign.
Second Edition AD&DEdit
- 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 BeyondEdit
- 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.
3e offers a table that indicates that 1 gp can buy a goat or a pound of cinnamon. Magical Items can range in value from the low 12 gp, 5 sp (sometimes described as 12.5 gp) single-use 0-level scroll to artifacts valued at hundreds of thousands (or even over a million) gold pieces.
Gold coins in the real world Edit
Roman gold coins Edit
Gold was used for coinage very infrequently until the time of Julius Caesar, who introduced a standardised coin called aureus, which was struck regularly. It weighed 8 grams, about 1/40 of a Roman pound, but later its weight decreased to 1/45 of a pound in the time of Nero and to 1/50 of a pound in the time of Caracalla. The aureus had a fixed value of 25 denarii (Roman silver coin). Emperor Constantine I introduced the solidus to replace the aureus. Solidi were wider and thinner than the aureus, with the exception of some dumpy issues from the Byzantine Empire. The weight and fineness of the solidus remained relatively constant throughout its long production, with few exceptions. Fractions of the solidus known as semissis (half-solidi) and tremissis (one-third solidi) were also produced.
There were very few gold coins minted during the middle ages with gold more often being made into jewelry, lavish items for personal use, or holy items. When gold was used as money the weight was more important than the form the metal took and it was mainly used to settle debts between kingdoms.
Copper and silver coins as well as barter were the way average transactions were carried out.
British gold coins Edit
The noble was the first English gold coin produced in quantity, having been preceded by the twenty pence coin and the florin (also called double leopard) earlier in the reigns of King Henry III and King Edward III, which saw little circulation. The coin was introduced during the second coinage (1344-1346) of King Edward III, when the coin weighed 138.5 grains (9.0 grams); during the kings' third coinage (1346-1351) the weight of the coin was reduced to 128.5 grains (8.3 grams), while in his fourth coinage (1351-1377) it became even lighter, at 120 grains (7.8 grams).
A gold sovereign is a gold coin first issued in 1489 for Henry VII of England and still in production as of 2006 (equal to a pound sterling). Those original sovereigns were 23 carat (96%) gold and weighed 240 grains or one-half of a troy ounce (15.6 grams). Henry VIII reduced the purity to 22 carats (92%), which eventually became the standard; the weight of the sovereign was repeatedly lowered until when it was revived after the Great Recoinage law of 1816, the gold content was fixed at the present 113 grains (7.32 g), equivalent to 0.2354 Troy ounces. Sovereigns were discontinued after 1604, being replaced by unites, and later by laurels. Production of sovereigns restarted in 1817.
The guinea coin of 1663 was the first British machine-struck gold coin. The coin was originally worth one pound, which was twenty shillings; but rises in the price of gold caused the value of the guinea to increase, at times as high as thirty shillings. 44½ guineas would be made from one Troy pound of 11/12 finest gold, each weighing 129.4 grains. In 1670 the weight of the coin was reduced from 8.4–8.5 g to 8.3–8.4 g, but the price of gold continued to increase, and by the 1680s the coin was worth 22 shillings. The diameter of the coin was 25 millimetres throughout Charles II's reign, and the average gold content (from an assay done in 1773) was 0.9100.
General circulation US gold coins Edit
The United States had general circulation gold coins from 1792 to 1933. Four of these coins are officially known as "Eagles".
Gold dollar: Minted from 1849 to 1889. While the coin weighed 1.672 g it varied in diameter (12.7 mm to 14.3 mm)
Quarter Eagle ($2.50): 17 mm diameter; 4.37 g (nearly 104 to a pound)
Three-dollar piece: Minted 1854 to 1889; 20.5 mm diameter; 5.015 g (about 90 to a pound)
Half Eagle ($5): 21 mm diameter; 8.75 g (nearly 52 to a pound)
Eagle ($10): 27 mm diameter; 17.5 g (nearly 26 to a pound)
Double Eagle ($20): minted 1849-1933. 34 mm diameter; 33.4362 grams (nearly 14 to a pound)
Gold coins in different campaign settings Edit
Gold Pieces are called Golden Lions in Cormyr, Dantars in Amn, Bicentas in Calimport, Dragons in Waterdeep, Shilmaers in Cormanthyr and Dinars in Southern Lands. Sembia mints five-sided coins of the same weight called Golden Lions (not to be confused with the eponymous Cormyrean gold pieces.
The Dragonlance Campaign Setting greatly devalues the intrinsic worth of the gold piece and replaces it with the Steel Piece (Stl) as the default value in the rulebooks, with 1 Stl = 1 standard gp. In the Setting itself, the actual value of a gp relative to the other coin types depends on the region; in some areas (Seeker Lands) the gp is literally worthless, while in others it may be worth between 1/10th Stl, 1/40th Stl or 1/50th Stl.
- ↑ Dungeons & Dragons Basic Rules pp B20 4th ed. Jan 1981 - "Moldvay red book"
- ↑ The 1974 Edition had the following values for electrum: "If Electrum is added it is optionally worth either twice or half the value of Gold."
- ↑ Dungeons & Dragons Basic Rules book 2, page 39 1st ed. 6th printing - "White box"
- ↑ Dungeons & Dragons Basic Rules page 34 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 Dungeon Master's Guide (1st edition) 1979 pp 25
- ↑ Advanced Dungeons & Dragons Dungeon Master's Guide (1st edition) 1979 pp 86
- ↑ "Only Train When You Gain" Dragon #97
- ↑ Advanced Dungeons & Dragons Player's Handbook pp 66 2nd ed. 1989
- ↑ SRD
- ↑ David Nalle "For the Sake Of Change" Dragon #63 pg 67
- ↑ GURPS Middle Ages I pg 60
- ↑ Dragonlance Adventures Hardcover, 1987