Citrine is usually from Brazil, mostly the  state of Rio Grande do Sul, though Russia, France and more recently, the African Congo has also produced natural citrine with an unparalleled Champagne gold colour . The name citrine is derived from the old French word for lemon, citrin.

Sometimes citrine is referred to as gold topaz, madeira topaz, Brazilian topaz, topaz citrine and topaz quartz (or just topaz!), which is incorrect and often a ploy of unscrupulous dealers to sell citrine for the more expensive yellow topaz. This name was used in the past in reference to the colour, which is similar to the colour of yellow topaz.

Since most citrine on the market started its life as amethyst which was heated to 878 degrees or higher to change its colour, natural citrine is surprisingly uncommon.
 

The heat treated variety (left) is nothing like natural citrine (right), and can be identified by a more orangey-amber colour and, in raw crystal, shape. Natural citrine never has a reddish tint and the characteristic stout taper of raw amethyst is also different. Citrine shares its form with clear quartz - more elongated and usually with parallel sides.

From an energetic and healing viewpoint, it's just a waste of good amethyst.
 

"It activates opens and energizes the naval and solar plexus chakras, directing, via personal power, creativity, and intelligent decisiveness, the energy necessary to enhance the physical body. It stimulates both mental focus and endurance."

It brightens and cleanses the aura and promotes a happy disposition, helping one to overcome intellectual and emotional problems. It has a positive influence on relationships, helping one to perceive obstacles and their solution optimistically. Essentially, citrine is a kind of "touchstone" for negative energies, transmuting them into a positive state.