Quartz, but with souvenirs

Quartz is silicon dioxide. As it grows from silica‑rich fluids, it can trap foreign guests—other minerals, tiny droplets of the very fluid it grew from, even pockets of gas. If the guest keeps its own shape it’s a solid inclusion; if it’s a droplet, it’s a fluid inclusion; if the inclusion is a void shaped like a crystal, it’s a negative crystal.

Why some inclusions align

Many needles are epitaxial—they grow in preferred orientations dictated by the quartz lattice. That’s why rutile often crosses at neat 60°/120° angles and tourmaline rods tend to run parallel to the quartz c‑axis.

Capture during growth

As quartz faces advance, they can overgrow existing micro‑crystals or trap bits of the surrounding solution. This is how you get rutilated and tourmalinated quartz—needles were there first, quartz wrapped them in glass‑clear silica.

Stop, start, repeat

Quartz often grows in pulses. A pause leaves a dusty layer; restarting creates a phantom—a ghostly outline of an earlier crystal stage preserved inside the newer crystal.

Seeps & heals

Tiny fractures may let in chlorite‑rich or iron‑rich fluids that decorate the crack. Later quartz heals the seam, preserving dendrites, moss, or confetti‑like flakes as permanent artwork.

Fluid time capsules

Fluid inclusions are droplets of ancient water (sometimes oil) trapped during growth. Two‑phase inclusions show a liquid + gas bubble; warm the stone slightly and you’ll see the bubble dance.

Negative crystals

These are voids that mimic crystal shapes—often tiny quartz‑shaped cavities. They can hold a film of fluid or a bubble and look like perfectly faceted miniatures floating inside.

Color from guests

Chlorite infuses green, hematite red, goethite/lepidocrocite orange, rutile gold. Even colorless quartz becomes dramatic when its guests bring paint.

What you might see

• Hair / needles — golden rutile, black tourmaline, green actinolite.
• Confetti — shimmering flakes of hematite or lepidocrocite.
• Moss / gardens — chlorite clouds, earthy oxides (“lodolite”).
• Fireworks — starry, cross‑hatched sagenite networks.
• Phantoms — faint inner triangles mirroring the outer tip.
• Enhydros — a mobile bubble in a clear pocket.
• Negative crystals — tiny, faceted voids—like quartz within quartz.

How light plays

Needles catch side‑light and blink; platelets flash like tiny mirrors; chlorite softens the interior, giving depth. A black card behind the crystal boosts contrast; a pinpoint light brings inclusions to life.

Photo tip: Use one small light at ~30° and move the stone, not the light. You’ll see needles “turn on” as they hit the sweet angle.

Rutile vs. actinolite

Rutile needles are mirror‑bright and often meet at tidy angles; actinolite looks silky, fibrous, sometimes slightly curved with softer sheen.

Phantoms, not scratches

Phantoms are inside the quartz and move with the stone when you tilt. Surface scratches catch light only at certain angles and stay put relative to your viewpoint.

Fluid fun

Warm the stone in your hand: the bubble in a two‑phase inclusion grows/shrinks or slides. Under longwave UV, hydrocarbon inclusions sometimes glow blue‑white.

Negative crystals

Look for perfectly faceted voids with crisp edges—miniature quartz shapes trapped inside. A tiny bubble along one face seals the deal.

Needle orientation

In many crystals, needles run parallel to the c‑axis (crystal length). Rotate the specimen—if needles “switch on” in bands, you’re seeing alignment play with the light.

Edge check

Where inclusions reach the surface, the polish can undercut slightly. That’s normal—just a reminder to handle edges gently.

Crackle‑dyed quartz

Heat‑shocked quartz injected with dye pools in fractures. Under 10× you’ll see branchy crack networks filled with uniform color—very different from real mineral grains.

Glass “strawberry”

Glass with coppery glitter (aventurine glass) is smooth, bubble‑rich, and soft. Natural strawberry quartz shows tiny platelets/needles within quartz and Mohs ~7 toughness.

“Super Seven” marketing

Trade names promise many species in one stone; in reality, most show a few iron oxides and occasional rutile. Enjoy the beauty—just label by what you see.

Dendritic vs. garden

Dendrites are tree‑like Mn/Fe oxides along a plane; garden inclusions are volumetric mossy clumps (chlorite). One is a flat “painting,” the other a tiny terrarium.

Surface coatings

Oxide skins on the outside can mimic inclusions. Check edges and broken spots—if the “inclusion” wipes away or chips off, it was a coating.

Quick checklist

• Inclusions show depth & parallax as you tilt.
• Mineral shapes are coherent (needles, plates, cubes) not puddled dye.
• Quartz hardness (7) and conchoidal chips on fresh breaks.

Global highlights

• Brazil (Minas Gerais & Bahia) — rutilated & tourmalinated quartz; lush “garden” pieces.
• Pakistan & Afghanistan — actinolite “green hair” quartz; fine tourmaline rods.
• Alps & Himalaya — chlorite phantoms; negative crystals; water‑clear tips.
• South Africa (Messina) — rare ajoite/papagoite blue inclusions.
• Arkansas, USA — clear crystals with titanium oxide curiosities.
• Madagascar — scenic lodolites and hematite “fire” inclusions.

What varies by locale

Needle type, density, and color palette shift with host rock chemistry and temperature. Alpine pieces tend to be ultra clear with crisp phantoms; Brazilian gardens favor mossy volume; Pakistani material excels at silky green fibers.

Everyday care

• Quartz is tough (Mohs 7) but tips chip—handle like you would a fine point.
• Use lukewarm water + mild soap + soft brush; rinse & dry.
• Avoid ultrasonics/steam on enhydros and heavily included stones.

Display & storage

• Side‑light around 30° and a dark backdrop make inclusions pop.
• Keep away from high heat—fluid inclusions can expand and stress the stone.
• Store separately from softer gems (quartz tends to win scratch contests).

Lapidary tips

• Orient the dome so needles traverse the apex or the bubble sits centered.
• Pre‑polish thoroughly (to 3k–8k) before final cerium/oxide on soft pads; light pressure avoids “orange peel.”
• Stabilize edge‑reaching inclusions before cabbing; consider bevels to protect exposures.