Gagarinite-(Y) is a rare sodium-calcium-yttrium fluoride mineral typically found in evolved alkaline pegmatites. Collectors look for small, prismatic crystals often embedded in feldspar or associated with rare-earth element minerals like zircon and astrophyllite.
Is this gagarinite-(y)?
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 gagarinite-(y) with a known reference. Gagarinite-(Y) sits at Mohs 4.5, 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 to dull.
- 4Match the color rangeCompare against the expected color range: yellow, cream white, light brown, pink.
- 5Look at form & habitCrystal system: hexagonal. Typical habit: massive.
Often confused with
Gagarinite-(Y) vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside gagarinite-(y)
Minerals reported to co-occur with gagarinite-(y). Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- NaCaYF₆
- Mohs hardness
- 4.5
- Density
- 4.11-4.29 g/cm³
- Streak
- White
- Luster
- Vitreous to dull
- Transparency
- Transparent to translucent
- Crystal system
- Hexagonal
- Crystal habit
- Massive
- Cleavage
- One direction, prismatic, distinct
- Rarity
- Rare
- Uses
- Collector
- Host rock
- As disseminations, segregations, and in veins and miarolitic cavities within Na-metasomatized alkalic granites and quartz-syenites
Where rockhounds find gagarinite-(y)
Classic worldwide localities
- Found at Washington Pass, Okanogan Co., USA
- Bol’shoi and Malyi stocks, Verkhne-Espe alkaline massif, Tarbagatai Range, and the Katugino massif, Irkutsk region, Kazakhstan
- Found in the Erzin alkaline massif, southeastern Tuva, Russia
- Occurs in the vicinity of Lake Gjerdingen, Nordmarka, Norway
Field-hunting tip
Where it forms: As disseminations, segregations, and in veins and miarolitic cavities within Na-metasomatized alkalic granites and quartz-syenites. If you start seeing riebeckite, pyrochlore, zircon in float, you are in the right ground. Typical habit: massive. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify gagarinite-(y)?+
Where is gagarinite-(y) found?+
Is gagarinite-(y) safe to handle?+
What rocks look like gagarinite-(y)?+
What minerals are found with gagarinite-(y)?+
What kind of rock does gagarinite-(y) form in?+
What is gagarinite-(y) used for?+
Find gagarinite-(y) on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
