Chevkinite-(Ce) is a rare complex silicate mineral primarily occurring in alkaline igneous rocks. It is most often found as opaque black prismatic crystals or massive aggregates and is notable for its thorium content, which makes it radioactive.
Is this chevkinite-(ce)?
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 chevkinite-(ce) with a known reference. Chevkinite-(Ce) sits at Mohs 5.5-6, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: black.
- 3Read the lusterHold the specimen under a strong light. Luster: resinous to dull.
- 4Match the color rangeCompare against the expected color range: brownish black, dark red.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: acicular, massive, metamict.
Often confused with
Chevkinite-(Ce) vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Streak differs, so Chevkinite-(Ce) leaves black, Allanite leaves gray; luster reads resinous to dull on Chevkinite-(Ce) and submetallic on Allanite.
How to tell apart: Streak differs, so Chevkinite-(Ce) leaves black, Perrierite-(Ce) leaves brown.
How to tell apart: Streak differs, so Chevkinite-(Ce) leaves black, Epidote leaves grayish white; luster reads resinous to dull on Chevkinite-(Ce) and vitreous, pearly, somewhat resinous on Epidote.
Often found alongside chevkinite-(ce)
Minerals reported to co-occur with chevkinite-(ce). Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Ce₄(Ti,Fe,Fe)₅O₈(Si₂O₇)₂
- Mohs hardness
- 5.5-6
- Density
- 4.53-4.67 g/cm³
- Colors
- Streak
- Black
- Luster
- Resinous to dull
- Transparency
- Opaque
- Crystal system
- Monoclinic
- Crystal habit
- Acicular, massive, metamict
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- As an accessory mineral in some granites, and in pegmatites associated with alkalic granite and syenites; in air-fall ash deposits
Where rockhounds find chevkinite-(ce)
Classic worldwide localities
- Aquarius Mountains, Mohave Co., Arizona, USA
- Jemez Mountains and Pueblo Mesa, Rio Arriba Co., New Mexico, USA
- Onion Creek, Grand Co., Utah, USA
- Yellowstone National Park, Wyoming, USA
- Ilmen Mountains, Southern Ural Mountains, Russia
- Keivy massif, Kola Peninsula, Russia
Field-hunting tip
Where it forms: As an accessory mineral in some granites, and in pegmatites associated with alkalic granite and syenites; in air-fall ash deposits. If you start seeing titanite, monazite, apatite in float, you are in the right ground. Typical habit: acicular, massive, metamict. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify chevkinite-(ce)?+
Where is chevkinite-(ce) found?+
Is chevkinite-(ce) safe to handle?+
What rocks look like chevkinite-(ce)?+
What minerals are found with chevkinite-(ce)?+
What kind of rock does chevkinite-(ce) form in?+
What is chevkinite-(ce) used for?+
Find chevkinite-(ce) on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
