AAA Diamond Apophyllite on Blue Chalcedony with Red Heulandite

AAA Diamond Apophyllite on Blue Chalcedony with Red Heulandite

Overview

This large, high-grade specimen features a dense formation of highly reflective “diamond” apophyllite crystals set within a blue chalcedony-lined cavity, enhanced by distinct red heulandite inclusions throughout the formation.

The contrast between the sharp, glassy apophyllite crystals, the smooth blue chalcedony base, and the warm red tones of heulandite creates a visually layered and mineralogically complex display piece. Cut into a freestanding form, the internal crystal structure is fully exposed, revealing multiple stages of mineral growth within a single specimen.

Key Features

Minerals: Apophyllite, Chalcedony (Quartz), Heulandite (Zeolite group)

Grade: AAA (high crystal density, strong lustre, well-defined formations)

Colour:

Colourless to pale blue apophyllite

Blue-grey chalcedony base

Red heulandite inclusions

Crystal Systems:

Apophyllite: Tetragonal

Heulandite: Monoclinic

Formation: Multi-phase mineral growth within a volcanic cavity

Lustre: Vitreous (apophyllite), pearly to vitreous (heulandite)

Transparency: Transparent to translucent

Dimensions

Weight: 323 grams

Size: 9 cm x 5.5 cm

Geological & Scientific Notes

This specimen formed in a volcanic cavity through multiple stages of mineral deposition:

Chalcedony (SiO₂) formed first, lining the cavity as a microcrystalline silica layer

Apophyllite crystallised from hydrothermal fluids, forming sharp, reflective tetragonal crystals

Heulandite, a zeolite mineral, formed later under changing temperature and chemical conditions, producing the distinctive red inclusions visible throughout the piece

The presence of both apophyllite and heulandite is characteristic of zeolite mineral environments, where shifting fluid chemistry allows multiple minerals to crystallise sequentially within the same space.

Why This Piece Stands Out

Large, freestanding display specimen

Multi-mineral composition (apophyllite + chalcedony + heulandite)

Strong contrast between colourless crystals and red inclusions

High-lustre “diamond” apophyllite with excellent light reflection

Dense internal crystal structure with depth and texture

AAA grade with clean, well-balanced formation

Care & Handling

Handle carefully — zeolite minerals can be delicate

Avoid prolonged water exposure

Clean with a dry, soft brush only

Store/display in a low-contact area