Diamond Apophyllite on Blue Chalcedony with Peach Stilbite & Calcite (AAA Grade)

Diamond Apophyllite on Blue Chalcedony with Peach Stilbite & Calcite (AAA Grade)

Overview
This multi-mineral specimen showcases highly reflective “diamond” apophyllite crystals set across a soft blue chalcedony base, complemented by peach-toned stilbite blades and a distinct cubic calcite crystal.

The contrast in crystal habits is what makes this piece stand out — sharp, glassy apophyllite points, smooth microcrystalline chalcedony, bladed stilbite formations, and a geometric calcite cube all formed together within the same environment. This combination reflects multiple stages of mineral deposition, making it both visually striking and geologically complex.

Key Features
Minerals: Apophyllite, Chalcedony (quartz), Stilbite, Calcite
Grade: AAA (high clarity apophyllite, defined crystal structures, strong lustre)
Colour:
Colourless to pale blue apophyllite
Soft blue chalcedony base
Peach/orange stilbite
Colourless calcite cube
Crystal Systems:
Apophyllite: Tetragonal
Calcite: Trigonal (cubic habit visible)
Stilbite: Monoclinic
Formation: Multi-phase mineral growth within volcanic cavity
Lustre: Vitreous (apophyllite, calcite) to pearly (stilbite)
Transparency: Transparent to translucent

Dimensions
Weight: 59 grams
Size: 5.5 cm x 4.1 cm

Geological & Scientific Notes
This specimen formed within a volcanic cavity where mineral-rich fluids deposited different minerals over time in distinct stages:

Chalcedony (SiO₂) formed first as a microcrystalline silica base from gel-like silica deposits
Apophyllite crystallised later from hydrothermal fluids, forming well-defined tetragonal crystals with high reflectivity

Stilbite, a zeolite mineral, developed in bladed formations under lower temperature conditions, giving the soft peach colouring

Calcite (CaCO₃) formed last, producing the cubic crystal through its cleavage structure (despite belonging to the trigonal system)

The presence of multiple minerals in one piece indicates changing chemical conditions during formation — a key factor that increases both scientific interest and collectability.

Why This Piece Stands Out
Multi-mineral specimen (4 distinct minerals in one piece)
Strong contrast in crystal shapes: cubic, bladed, and pointed
High-lustre “diamond” apophyllite with excellent light reflection
Rare combination of blue chalcedony with peach stilbite
Visible calcite cube adding structural uniqueness
AAA grade with clean, well-defined formations

Care & Handling
Handle carefully — apophyllite and stilbite are delicate
Avoid water exposure (zeolite minerals can degrade over time)
Clean using a dry, soft brush only
Store separately to protect crystal edges