Pull a glowing honey-yellow six-pointed flower crystal out of Brazilian or Russian pegmatites and anyone shouts 'Hexagonal Quartz or Beryl!'—until your 10x loupe catches sharp diagonal herringbone striations meeting cleanly in 6 tiny V-shaped center valleys! Strictly Orthorhombic (Pmnb), hard Mohs 8.5 Chrysoberyl (BeAl2O4) pulls off geometry magic by repeatedly twinning at ~59.8° on {130} planes—welding 3 individuals into symmetrical 6-spoke Cyclic Trillings ('Sixlings')! Assemble twins live on canvas, flip daylight-green to ruby-night Alexandrite, and spot fake carved Beryl impostors!
Wait — Did You Know?Discovered perched starkly atop snowy white albite-muscovite pegmatites in Brazil's Espirito Santo, complete sharp Chrysoberyl Sixlings look like bronze mechanical gear-snowflakes—each of the 6 arms displaying unmistakable diagonal 'herringbone' chevrons pointing toward the center!
Select Specimen or Control Sample (8 Profiles)
Click any Twinned Chrysoberyl, Sixling Alexandrite, or hexagonal lookalike to verify re-entrant V-notches and herringbone silk:
Why does this happen atom-by-atom? Read the 3-step physics strip below, then keep scrolling for Chapter 2 (Microscopic Atomic Zoom) and Chapter 3 (Interactive Real vs. Fake Split Loupe).
How The Crystal Physics Works (3-Step Flowchart)
Visual Mechanism Breakdown
1. Orthorhombic Chrysoberyl Ratio b/a Sits Almost Dead On sqrt(3)
Because the crystal's side lengths match a near-1:1.72 ratio (59.8° diagonal angle), attaching twin crystals edge-to-edge along {130} swings precisely 60° per junction!
2. Three Interlocking Crystals Wrap Completely Around Into A 360° Star
Just three Orthorhombic blades cycling around one central nucleus generate six symmetric pointed arms—creating nature's sharpest fake hexagon out of pure rectangular crystal geometry!
Diagonal growth grooves march symmetrically inward along each blade arm, meeting sharply at center seams to distinguish cyclic twins effortlessly from flat Beryl hexagons.
Chapter 2 of 3 • Microscopic Atomic Lattice Zoom
Inside The Lattice: Colatina Espirito Santo Chrysoberyl Sixling
❌ MYTH: Any mineral crystal shaped like a 6-pointed star or 6-sided flower must belong to the Hexagonal Crystal System.
✅ FACT: Textbook trap busted cleanly by Chrysoberyl, Aragonite, and Cerussite! All three are strictly ORTHORHOMBIC minerals whose ~60° {130}/{110} twin angles mimic 6-fold symmetry via cyclic trillings!
❌ MYTH: Chrysoberyl is just a yellow subspecies of Beryl (like Heliodor) because both contain Beryllium.
✅ FACT: Completely different minerals! Beryl is a softer Mohs 7.5–8 hexagonal aluminum silicate (SG 2.7), whereas Chrysoberyl is an ultra-hard Mohs 8.5 orthorhombic beryllium aluminate oxide (SG 3.72) sharing ZERO silicate tetrahedra!
❌ MYTH: All rough six-rayed green crystals in mica schist turn bright red at night like Russian Alexandrite.
✅ FACT: Careful—chromium-poor or vanadium-rich specimens stay green under all lights; ALWAYS verify true red-purple incandescent color change before valuing rough twins as Alexandrite!
Chapter 3 of 3 • Interactive Real vs. Fake Split Loupe
Authentic Specimen vs. Fake / Impostor Drag-Loupe
Drag the divider left/right — toggle Probe Mode for forensic lighting, cleavage & bubble inspection.
60-Second Pocket Field Test Checklist
Examine the outer perimeter under 10x: look for small inward V-shaped re-entrant notches nestled between the 6 flower petals where adjacent Orthorhombic individuals collide.
Tilt crystal faces toward point light to catch diagonal herringbone growth lines marching toward each central radial seam.
Distinguish quickly from lookalike hexagonal green Beryl or Aragonite by checking Mohs 8.5 extreme hardness (scratches quartz effortlessly) and dense SG 3.72 heft.
For Cat's-Eye Cymophane cabs, test cleanly with one flashlight tilted sideways to verify the classic bright creamy-milk vs honey-clear shadow contrast.
Collector Caution & Fake Alert: CUTTING & IMITATION NOTE: Leaving famous rough Brazilian Colatina Sixlings completely uncut inside matrix often preserves higher collector treasure value than faceting tiny clear corners—while on cut Cat's-Eye gems, look for genuinely translucent 'milk-and-honey' contrast rather than dead grey synthetic fiber-optic glass!
Collector Field Guide & Mineralogy Deep Dive
Locality, Chemistry & Optical Notes
🇧🇷 Colatina Brazil's Pegmatite Gear-Wheels
Inside weathered feldspathic pockets across Espirito Santo, golden-yellow Chrysoberyl blades intergrew into museum-grade Sixlings standing starkly proud atop snow-white Albite and silvery Muscovite blades—serving as mineralogy's cleanest geometry lesson.
👑 1834 Urals: Emerald By Day, Ruby By Candlelight
Discovered along Russia's Tokovaya River right on future Tsar Alexander II's coming-of-age birthday, dark mica-embedded Sixling crystals stunned court gemologists by glowing pine-emerald outdoors and shifting velvet raspberry-purple beside candle sconces!
👁️ Decoding 'Milk-And-Honey' On Genuine Cymophane
Shine a penlight 45° sideways across a top Sri Lankan Cat's-Eye cabochon: the illuminated side beams bright cream-milk while the shaded half glows rich translucent caramel honey separated cleanly by a razor silver band!
🔬 Optical Cross-Polarization Inside A Sixling Wafer
Slip a thin sliced Sixling cleanly under crossed polarizers: unlike single Beryl slabs that darken uniformly every 90°, opposing pie sectors of a Chrysoberyl Sixling blink bright yellow and dark amber at staggered angles—proving 3 distinct crystal orientations!
Diagnostic Specimen Comparison Matrix
Quick Laboratory & Collector Reference
Mineral / Control
Formula & System
Key Physical Metric
Diagnostic Tell
Classic Locality
Espirito Santo Sixling
BeAl2O4 | Orthorhombic
Mohs 8.5 | SG 3.72
6-spoke cyclic trilling + herringbone V seams
Colatina, Minas/ES Brazil
Ural Alexandrite Sixling
BeAl2O4:Cr3+ | Pmnb
Mohs 8.5 | SG 3.73
Green daylight <-> ruby-red candle + 6 spokes
Tokovaya Urals, Russia
Chrysoberyl V-Twin
BeAl2O4 (2-Blade Twin)
Mohs 8.5 | SG 3.72
Sharp heart/butterfly wing contact seam
Brazil / Madagascar
Cymophane Cat's-Eye
BeAl2O4 + TiO2 Tubes
Mohs 8.5 | RI 1.75
Razor silver eye splitting milk & honey halves
Sri Lanka / Orissa India
Aragonite Trilling
CaCO3 | Orthorhombic
Mohs 3.8 | SG 2.94
Same ~60° cyclic law; soft + fizzes cold acid
Molina de Aragón, Spain
Hexagonal Green Beryl
Be3Al2Si6O18
Mohs 7.8 | SG 2.72
True 6-fold prism; zero twin seams or V-notches
Unrelated Control
Frequently Asked Mineralogy Questions
Collector & Lab Answers
How can Orthorhombic Chrysoberyl look like a 6-pointed hexagonal star crystal?
Its unit-cell geometry creates an angle of ~59.8° along {130} twinning planes—allowing three Orthorhombic blades to fuse cleanly together in a 360° circle ('cyclic trilling' or 'Sixling') with 6 symmetric radial spokes.
How do you tell a Chrysoberyl Sixling apart from a genuine Hexagonal Beryl or Quartz crystal?
Look closely at crystal faces under a 10x loupe: Sixlings show tiny V-shaped inward notches between crystal points AND diagonal herringbone striations converging cleanly at 6 internal twin seams, whereas true hexagonal crystals have continuous parallel lines.
What is the difference between Chrysoberyl and Beryl?
Despite both containing Beryllium, Chrysoberyl is a much harder (Mohs 8.5), denser (SG 3.72) Beryllium Aluminate oxide (BeAl2O4), whereas Beryl is a softer (Mohs 7.5–8), lighter (SG 2.7) Beryllium Aluminum Silicate.
Does every Chrysoberyl change color like Alexandrite?
No—only Chromium-bearing Chrysoberyl ('Alexandrite') flips dramatically from green daylight to red-purple incandescent light. Iron-bearing golden Chrysoberyl, Cymophane Cat's-Eye, and pure Vanadian mint Chrysoberyl do not reverse red.
Why do Ural Mountains Alexandrites famously grow inside Sixlings?