High CRI Penlight

Tiny concentrated white spot for field checks, inclusions, fire, and fractures

Typical price$ 10 - 120

PortabilityHighly portable

Field notePocket penlight or mini torch, battery powered

How to use it

Clean the stone surface so dust and grease do not imitate inclusions
Hold the penlight very close to the side or pavilion of the stone without touching it
Use the smallest concentrated beam available and move it slowly around the stone
Watch for inclusions, feathers, filled fractures, color zoning, and internal reflections
For dispersion, aim the spot through the crown or pavilion and rotate the stone until fire appears
For spectroscope work, place the beam behind or through the stone to create a strong transmitted light path
Compare side lighting, backlighting, and reflected lighting before drawing conclusions

Reading tips

Search for high CRI, neutral white, medical penlight, inspection penlight, or mini LED torch
A narrow focused beam is more useful than a wide flood beam for inclusions and fractures
CRI 90 or higher is preferable; very blue LEDs can distort body color and fluorescence impressions
Side lighting reveals silk, needles, fractures, and surface-reaching fissures better than overhead light
A concentrated beam helps detect doubling of back facet edges in doubly refractive stones
Keep the beam moving on opal, amber, pearls, turquoise, and filled stones; heat and intense light can be risky
This is the pocket version of a fiber optic illuminator, not a replacement for lab lighting