Electrum

Electrum was a naturally occurring silver–gold alloy, with half the value of pure gold, such that one electrum piece (ep) is worth ½ gold piece (gp). which makes electrum worth 25 gp per pound as a trade good.

Value and terminology
Most of Faerûn used “standard rates of exchange for coinage”, based on the silver and gold standard, with copper pieces (cp) worth 1/100 of a gold piece (gp), and silver pieces (sp) worth 1/10 of a gp. Electrum pieces (ep) were worth 1/2 of a gp, and platinum pieces were worth 10 gp.

Each coin is approximately 30.6 mm in diameter and weighs approximately 9 grams each (or 50 to one pound).

Electrum pieces were called blue eyes in Cormyr, centaurs or decimes in Amn, centarches in Calimport,, and moons in Waterdeep.

Throughout the heartlands, common electrum pieces—round Cormyan eyes; diamond-shaped Sembian electrums, Calimshite tazos and zonths, and Amnite centaurs—were called “blue eyes”, regardless of origin.

Exceptions included:
 * The original shining blue crescent-shaped electrum moon of Silverymoon—was a coin worth 1 ep throughout the Realms, but twice that much in the city itself.
 * The harbor moon of Waterdeep—was a cresent shaped Waterdhavian coin of platinum inset with electrum, with a hole in its center. In Waterdeep it was valued at 50 gp and used for bulk transactions. Outside the city, harbor moons were valued between 2 gp, and 30 gp.
 * “In lieu of platinum pieces, Sembia mints electrum pieces (ep) known as blue-eyes, each equal in value to 5 gp.”

Other uses
The spell Khelben's warding whip used a pinch of powdered electrum as a material component.

The spell Leomund's secret chest could use a chest fashioned from bronze, copper, or silver, with fittings of electrum or silver.

Magical morning stars—known as storm stars—are crafted from electrum-plated steel, and can unleash a chain lightning effect.

An electrum mounting, allows witherite to be worn as a protection to necromantic attacks.

Two notable tomes—The Chambeeleon and The Tome of the Unicorn—had electrum pages, with the latter also having electrum covers.

If one of the twisted bands of a shoonring was made of electrum, this usually indicated that the ring contained multiple powers and enhanced the effects of the magics involved.

Conversion

 * AD&D (1st Ed.)
 * 200 cp = 20 sp = 2 ep = 1 gp = 1&frasl;5 pp
 * 100 cp = 10 sp = 1 ep = ½ gp = 1&frasl;10 pp


 * AD&D 2nd Ed.
 * 100 cp = 10 sp = 2 ep = 1 gp = 1&frasl;5 pp
 * &#8199;50 cp = &#8199;5 sp = 1 ep = ½ gp = 1&frasl;10 pp


 * D&D 3rd Ed.
 * 100 cp = 10 sp = 1 gp = 1&frasl;10 pp
 * Electrum pieces (ep) are not mentioned in the core rules, and common electrum pieces are not mentioned in the FRCS.


 * D&D 4th Ed.
 * 100 cp = 10 sp = 1 gp = 1&frasl;100 pp = 1&frasl;10,000 ad
 * Electrum pieces (ep) are not mentioned in the core rules, and only a Sembian electrum coin (worth 5 gp?) is mentioned in the FRCG.


 * D&D 5th Ed.
 * 100 cp = 10 sp = 2 ep = 1 gp = 1&frasl;10 pp
 * &#8199;50 cp = &#8199;5 sp = 1 ep = ½ gp = 1&frasl;20 pp

Background
The word “electrum” comes form a Greek word meaning pale-yellow, that was used both for the alloy, and for amber. Properties of amber led to to the modern English words “electron” and “electricity”.

Electrum alloys are primarily gold and silver (20–80% of each), with trace amounts of copper, platinum, and other metals. When used for Mediterranean coinage, the amount of gold (40–55%) was lower than local natural alloys (~70%) showing that the minters were adding silver to reduce the gold percentage. The color of electrum alloys (described as “white gold”, “pale gold”, or “green gold”) depended on the ratio of silver and gold (white- or pale-yellow) and trace elements such as copper (greenish-yellow).