Cathedral Quartz Identification Guide

What Cathedral Quartz Looks Like

Cathedral Quartz (also called cathedral lightbrary quartz) is a quartz crystal habit in which numerous smaller crystal points grow upward along the sides of a larger central crystal, like the towers and spires of a cathedral. Each step or "turret" has its own termination yet shares the parent crystal's body. It is usually clear to milky, sometimes smoky or amethystine, with a glassy luster and well-formed six-sided (hexagonal) prism faces.

Key Visual Traits

• A main hexagonal quartz crystal with multiple stepped points climbing its sides
• Each side point separately terminated
• Glassy luster; clear, milky, smoky, or purple body
• Distinct prism faces and horizontal striations across them

Step-by-Step Field-ID Checklist

1. Look at the form. The diagnostic feature is many parallel sub-crystals stepping up the sides toward a main termination.
2. Count the sides. Quartz prisms are hexagonal (six-sided).
3. Check striations. Quartz shows horizontal striations across the prism faces (perpendicular to the long axis).
4. Test hardness. Mohs 7; it scratches glass and resists a steel knife.
5. Examine the termination. Each turret ends in its own pointed cap.
6. Inspect clarity and color. Clear, milky, smoky, or amethyst-toned, with conchoidal fracture on broken edges.

Diagnostic Tests

• Hardness: 7 (scratches glass; not scratched by a knife).
• Fracture: Conchoidal, no cleavage.
• Streak: White.
• Density: About 2.65.
• Crystal system: Hexagonal/trigonal, six-sided prisms with horizontal striations.
• Acid/magnetism: Inert, non-magnetic.

Common Look-Alikes and How to Tell Them Apart

• Elestial (skeletal) quartz: Has etched, layered, terraced surfaces and many terminations all over, rather than orderly side-towers up a central crystal.
• Cactus/spirit quartz: A central crystal coated with tiny druzy points all around its sides, often amethyst; cathedral quartz has larger, stepped, parallel turrets, not a fine druzy coat.
• Scepter quartz: A larger crystal capping a thinner stem; different geometry.
• Calcite or fluorite groups: Calcite is softer (3) and fizzes in acid; fluorite is softer (4) with cubic cleavage. Quartz does neither.
• Glass replicas: Lack natural striations and may show bubbles; glass is softer and can be scratched by quartz.

Where It Is Typically Found

Cathedral quartz is a growth habit, not a separate mineral, and is collected mainly from Brazil (notably Minas Gerais), where large pegmatite and vein quartz crystals form. Other quartz-rich regions, including Madagascar and the Himalaya, also yield cathedral-form crystals. It is found in quartz veins, pegmatites, and pockets within granitic and metamorphic terrains.

Collector and Field Notes

Cathedral quartz is sold as a metaphysical and display specimen, so most pieces are kept as natural points rather than cut. Inspect the turrets to confirm they are genuine parallel growths sharing the parent crystal rather than separate crystals glued on; natural pieces show continuous, uninterrupted internal structure and matching striations across the towers. Larger Brazilian points can be heavily included or milky, which does not affect identification. Clean only with water and a soft brush; quartz is durable but the slender side-points can snap if knocked. Phantom inclusions and rainbows from internal fractures are common and harmless.