Mace

Source=Outer covering of the nutmeg seed
Flavor=Similar to nutmeg, but stronger
Best used=Dried or ground
Cooking use=Custards, spice cakes, fruit desserts

Nutmeg has long been alleged to have aphrodisiacal powers, giving rise to a variety of love potion concoctions and oftimes hilarious rituals. At the height of its value in Europe, nutmeg was carried around by ladies and gents as a demonstration of wealth. Diners would flourish tiny graters and grate their own in fancy restaurants. As a result, personal nutmeg graters became quite fashionable accoutrements, giving rise to intricate designs and shapes made of precious metals. These antique graters are now prized by collectors.
Mace is the lacy aril which is removed by hand from the outer shell of the nutmeg and then dried, becoming yellowish-brown mace. Mace is sold in whole pieces called "blades" or ground, and the color can often help you determine its origin. Orange-yellow blades most likely come from Grenada, while orange-red blades tend to be from Indonesia. Unlike most spices, ground mace has a longer shelf-life when stored properly.
Nutmeg contains a substance called myristicin, a narcotic with very unpleasant toxic side effects if taken in large quantities. Ingestion of small amounts of nutmeg is harmless to the body, however the consumption of one to three whole nutmegs (in excess of one teaspoon ground) can cause wild hallucinations, nausea, vomiting, and/or circulatory collapse within one to six hours after consumption. Very large doses can be fatal. Although nutmeg is said to counteract stomach distress from gas, do not try any home remedies without first consulting your physician. It is also an astringent and stimulant, as well as a purported aphrodisiac.