Lemon Quartz Identification Guide
Identify lemon quartz, a bright greenish-yellow quartz, and tell it apart from citrine, lemon opal, and yellow glass.
Read the full Lemon Quartz encyclopedia entry →
What Lemon Quartz Looks Like
Lemon quartz is a macrocrystalline quartz with a bright, slightly greenish lemon-yellow color, usually produced by heat treatment and/or irradiation of natural quartz. It is transparent with a brilliant vitreous luster and is most often seen as faceted gems or polished points. Rough crystals show the classic quartz six-sided (hexagonal) prism terminated by pyramidal faces. The yellow is typically very even and vivid, brighter and more acid-green than natural citrine.
Step-by-Step Field ID Checklist
- Confirm quartz crystal form. Look for six-sided prisms with horizontal striations across the prism faces and pyramidal terminations.
- Judge the color. Lemon quartz is a uniform, zesty greenish-yellow, brighter than the warm golden-brown of most citrine.
- Check clarity. Usually eye-clean and transparent.
- Test hardness against glass and a steel knife.
- Look for conchoidal fracture on chips.
Key Diagnostic Tests
- Hardness: Mohs 7; scratches glass and steel readily, a key separator from opal and glass.
- Streak: White.
- Fracture: Conchoidal; no cleavage.
- Density: ~2.65 g/cm3, heavier in the hand than opal or most glass.
- Acid: No reaction to HCl.
Common Look-Alikes and How to Tell Them Apart
- Citrine: Also quartz (Mohs 7) but warmer, more golden to brownish-orange; lemon quartz is cooler and greener. Both are usually heat-treated, but color tone separates them.
- Lemon opal: Common opal is softer (Mohs 5.5 to 6.5), lighter (density <2.2), waxy, and translucent rather than transparent; a hardness test settles it.
- Yellow glass: Glass shows mold seams, rounded internal bubbles, and is often softer (Mohs ~5.5); quartz scratches glass.
- Yellow topaz: Harder (Mohs 8) and denser (~3.5), with perfect basal cleavage that quartz lacks.
- Heliodor (yellow beryl): Slightly harder (7.5 to 8) and forms flat-faced hexagonal prisms; density ~2.7 to 2.9.
Where Lemon Quartz Is Typically Found
The base quartz is abundant worldwide, with much treated lemon quartz sourced from Brazilian and other large quartz deposits. Natural quartz forms in pegmatites, hydrothermal veins, and geodes globally. Because lemon quartz color is almost always the result of treatment, the 'find' is usually treated rough rather than naturally lemon-colored crystals.
Frequently asked questions
Is lemon quartz natural or treated?
Almost all lemon quartz on the market is produced by heat treatment and/or irradiation of natural quartz to create its bright greenish-yellow color. The underlying mineral is genuine quartz, but the vivid lemon hue is generally not natural.
What is the difference between lemon quartz and citrine?
Both are quartz with hardness 7, but lemon quartz is a cooler, brighter greenish-yellow while citrine is warmer and more golden to brownish-orange. The tone of yellow is the main visual distinction.
How can you tell lemon quartz from lemon opal?
Lemon quartz is hardness 7, transparent, and dense (about 2.65), scratching glass easily. Lemon opal is softer at 5.5 to 6.5, lighter (under 2.2), and waxy and translucent. A hardness and weight check distinguishes them quickly.
How do you tell lemon quartz from yellow glass?
Quartz scratches glass and shows no mold seams or rounded internal bubbles. Glass is softer and often contains spherical bubbles and seams from molding, while quartz shows six-sided crystal form in rough specimens.
Lemon Quartz identified by the community
Recent Lemon Quartz specimens identified with Rock Identifier.
