Tisinalite is a rare member of the eudialyte group typically found in agpaitic alkaline pegmatites. It is visually similar to other eudialyte-group minerals and usually requires analytical methods for definitive identification, appearing as small, distinct yellow to brownish crystals.
Is this tisinalite?
5-step field checkRun through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.
- 1Test the hardnessTry to scratch tisinalite with a known reference. Tisinalite sits at Mohs 5, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: white.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous.
- 4Match the color rangeCompare against the expected color range: yellow orange.
- 5Look at form & habitCrystal system: trigonal. Typical habit: subhedral crystals.
Often confused with
Tisinalite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside tisinalite
Minerals reported to co-occur with tisinalite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Na₃MnTiSi₆O₁₅(OH)₃
- Mohs hardness
- 5
- Density
- 2.66-2.69 g/cm³
- Colors
- Streak
- White
- Luster
- Vitreous
- Transparency
- Transparent to translucent
- Crystal system
- Trigonal
- Crystal habit
- Subhedral crystals
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Formed by the hydrothermal alteration of lomonosovite and barytolamprophyllite in alkalic pegmatites in a differentiated alkalic massif
Where rockhounds find tisinalite
Classic worldwide localities
- Mt. Koashva, Khibiny massif, Kola Peninsula, Russia
Field-hunting tip
Where it forms: Formed by the hydrothermal alteration of lomonosovite and barytolamprophyllite in alkalic pegmatites in a differentiated alkalic massif. If you start seeing koashvite, shcherbakovite, lamprophyllite in float, you are in the right ground. Typical habit: subhedral crystals. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify tisinalite?+
Where is tisinalite found?+
What rocks look like tisinalite?+
What minerals are found with tisinalite?+
What kind of rock does tisinalite form in?+
What is tisinalite used for?+
Find tisinalite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
