Yellow beryls occur in a range of yellow colours, from pale shades of lemon, to yellow tones both light and dark, to the yellow-orange of golden beryls. All shades of yellow may have green overtones.
Yellow beryl - may be used to describe all yellow stones. But the gem market may only use that description to indicate pale to mid-yellow colours. The more highly saturated stones may be described as 'golden yellow' or 'hediodor.' Honey yellow describes some stones.
Golden beryl - may describe bright yellow-orange colours with high saturation and not the weaker yellow and yellow-green tones.
Heliodor - may describe yellow-green coloured beryl, where the yellow colouring may be of varying shades. The name hediodor is Greek for 'Gift or present from the sun'.
Heliodor is also used to describe all yellow beryls in some gem markets.
Pale yellow beryl may be irradiated to improve the colour saturation.
Colourless beryl (goshenite) may be irradiated to produce yellow beryl. The colour remains stable.