UV-Reactive Optical Calcite with Rainbows – Maharashtra, India – 0.67 lbs

An impressive UV-Reactive Optical Calcite specimen from Maharashtra, India, featuring exceptional internal depth, broad transparent viewing areas, natural rainbow flashes, and a beautiful fluorescent response. Mounted upright on a custom display base, the specimen presents as a substantial architectural crystal with strikingly different appearances under ordinary and ultraviolet lighting.

Under white light, the calcite ranges from colorless and transparent to softly translucent. Large natural cleavage planes intersect throughout the interior, producing layered geometric reflections and window-like areas that allow light to travel deep into the specimen. Fine growth lines, internal veils, and smaller cleavage features add visual complexity without obscuring its overall optical character.

Several internal separations act as natural reflective surfaces, producing flashes of green, yellow, blue, violet, and other spectral colors as the specimen or light source is moved. These rainbows appear at different depths and angles, giving the crystal a constantly changing appearance during rotation.

Under ultraviolet illumination, the entire specimen develops a soft yet clearly visible pink-to-lavender fluorescent glow. The UV response reveals internal zoning and cleavage architecture that are less noticeable under ordinary lighting, while selected edges and internal features produce brighter blue-white highlights. Fluorescent color and intensity may vary according to the wavelength and strength of the UV lamp, ambient lighting, and camera settings.

Optical calcite is also known for pronounced birefringence, or double refraction. When viewed through sufficiently clear areas, text, lines, and other objects may appear doubled because the mineral separates incoming light into two rays.

Measuring approximately 3 × 2 × 3.5 inches and weighing 0.67 pounds, this is a substantial mounted calcite display. Its combination of clarity, geometric structure, internal rainbows, fluorescent response, and elevated presentation gives it both collector and educational appeal.

Specifications

Mineral: Calcite

Variety/Trade Description: UV-Reactive Optical Calcite with Rainbows

Locality: Maharashtra, India

Weight: 0.67 lbs (approximately 304 grams)

Dimensions: Approximately 3 × 2 × 3.5 inches

Color Under White Light: Colorless, transparent white, and softly translucent

Fluorescence: Pink-to-lavender overall response with brighter blue-to-blue-white highlights

UV Disclosure: Fluorescent color and intensity may vary according to UV wavelength, lamp strength, ambient lighting, exposure, and camera settings

Form: Large natural calcite cleavage specimen with broad optical viewing faces

Internal Features: Intersecting cleavage planes, geometric reflections, internal veils, growth lines, and rainbow-producing separations

Rainbow Effect: Multicolored spectral flashes created by light interacting with thin internal cleavage and fracture surfaces

Optical Property: Birefringence or double refraction through sufficiently transparent areas

Luster: Vitreous to glass-like

Transparency: Transparent to translucent

Crystal System: Trigonal

Chemical Formula: CaCO₃

Mohs Hardness: Approximately 3

Cleavage: Perfect rhombohedral cleavage in three directions

Mounting: Affixed to a custom display base produced in-house

Display: Elevated upright collector specimen

Condition: Natural calcite with inherent cleavage lines, internal fractures, inclusions, contacts, surface textures, and edge irregularities

Exact specimen shown

About Optical Calcite

Calcite is a calcium carbonate mineral known for its enormous variety of forms and its perfect rhombohedral cleavage. It separates along three consistent directions that do not meet at right angles, creating the slanted and intersecting geometric planes visible throughout this specimen.

Exceptionally transparent calcite is commonly called optical calcite because of its strong birefringence. When light enters the mineral, it separates into two rays traveling through the crystal differently. This can create two visible images when a clear section is placed over printed text or a fine line.

The internal rainbows are produced by a separate optical phenomenon. Thin natural cleavage separations and internal fractures interfere with and divide white light into spectral colors. Their position and intensity change with the viewing angle and direction of illumination.

Fluorescence occurs when a mineral absorbs ultraviolet energy and releases part of it as visible light. Trace elements, structural defects, inclusions, and different generations of calcite growth can influence the color and strength of the response. The specific fluorescent activator within this specimen has not been analytically determined.

Calcite is considerably softer than quartz and possesses perfect cleavage. It should be kept away from acids, harsh chemicals, prolonged soaking, and sudden temperature changes. Handle the specimen by its display base and clean it only with a soft, dry brush or gentle microfiber cloth.

Collector Notes

This specimen features:

• Substantial 0.67-pound optical calcite
• Natural material from Maharashtra, India
• Broad transparent-to-translucent viewing faces
• Pronounced internal geometric architecture
• Intersecting natural cleavage planes
• Window-like optical viewing areas
• Strong internal depth and layered reflections
• Multiple concentrated rainbow flashes
• Green, yellow, blue, violet, and multicolored spectral reflections
• Natural double-refraction properties
• Pink-to-lavender UV fluorescence
• Brighter blue-white fluorescent highlights
• Visible internal zoning under ultraviolet light
• Dramatically different white-light and UV appearances
• Custom display base produced in-house
• Elevated upright presentation
• Decorative, mineralogical, and educational appeal
• One-of-a-kind natural mineral specimen
• Exact specimen pictured

Perfect for collectors of optical calcite, fluorescent calcite, rainbow minerals, transparent minerals, birefringent crystals, UV-reactive minerals, Indian minerals, Maharashtra specimens, and natural optical phenomena.

Professionally packaged and shipped from Colorado.

You will receive the exact specimen shown.

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