Faden Quartz
Silicon dioxide (SiO2)
Tabular quartz crossed by a milky white thread-like line marking where the crystal repeatedly cracked and re-healed.
- Mohs hardness
- 7
- Color
- clear to milky white
- Type
- crystal
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Overview
Faden Quartz (from the German Faden, 'thread') is recognized by a distinctive milky-white line that runs through the crystal like a stitched seam. Crystals are usually flat and tabular, and the faden line records a fascinating growth story.
The thread forms when a crystal growing in a slowly opening rock fracture is repeatedly broken and re-healed; trapped fluid and gas inclusions concentrate along the break, creating the visible white string.
Classic faden quartz comes from Alpine-type fissures and from Pakistan's mountains. Collectors prize complete, undamaged crystals with a clear, well-defined thread.
Formation & geology
Faden Quartz forms in tectonically active fissures that slowly pull apart. A small quartz crystal first nucleates bridging the gap. As the fracture widens incrementally, the crystal repeatedly cracks at the same point and immediately re-heals with new quartz, trapping countless tiny fluid and gas inclusions along that line.
Over many cycles this builds the characteristic white thread running through a tabular crystal that grows in both directions away from the seam. The process requires slow, episodic stretching and a steady supply of silica-rich fluid, conditions typical of alpine cleft and similar fracture environments.
How to identify it
The diagnostic feature is a milky-white, slightly fuzzy thread-like line running through an otherwise clear, flat, tabular quartz crystal. Standard quartz properties confirm identity: hardness 7, glassy luster, conchoidal fracture, no cleavage, white streak.
The faden line is internal and consists of concentrated inclusions, not a surface scratch or applied marking. Distinguish it from phantom quartz (which shows ghostly former crystal outlines, not a single thread) and from ordinary fractured quartz (where cracks are sharp, reflective, and not healed). Genuine faden crystals are typically tabular and may show the thread anchoring two growth directions.
Uses & significance
Faden Quartz is collected almost exclusively as a mineral specimen, valued for the scientific and visual interest of its thread. Fine examples from Pakistan and the Alps are sought by collectors; some smaller pieces are wire-wrapped into jewelry.
Metaphysically it is described as a 'connection' stone linked to bonding and energy linkage, claims that are not scientifically supported. Its true significance is geological: the faden line is a visible record of repeated crack-and-heal growth in a slowly opening fracture, making it a favorite teaching specimen.
Frequently asked questions
What causes the white thread in Faden Quartz?
Repeated cracking and re-healing of the crystal in a widening fracture traps fluid and gas inclusions along a line, forming the white thread.
Why is Faden Quartz flat?
It grows in both directions away from the seam within an opening fissure, producing a characteristic tabular shape.
Where does Faden Quartz come from?
Classic sources include Alpine fissures in Europe and the mountains of Pakistan.
Is the faden line a crack?
It is a healed crack: a line of trapped inclusions inside solid quartz, not an open fracture.
Faden Quartz guides
In-depth guides for identifying, valuing, and understanding Faden Quartz.
