Radekškodaite-(La) is an extremely rare member of the gadolinite group, primarily found in granitic pegmatites. It appears as small, dark, subhedral to anhedral grains associated with other rare-earth element minerals and is typically identified through analytical methods like electron microprobe analysis.
Is this radekškodaite-(la)?
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 radekškodaite-(la) with a known reference. Radekškodaite-(La) sits at Mohs 6-7, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: brown.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous.
- 4Match the color rangeCompare against the expected color range: dark brown, black.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: anhedral grains.
Often confused with
Radekškodaite-(La) vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside radekškodaite-(la)
Minerals reported to co-occur with radekškodaite-(la). Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- (CaLa₅)(Al₄Fe)[Si₂O₇][SiO₄]₅O(OH)₃
- Mohs hardness
- 6-7
- Density
- 4.67 g/cm³
- Colors
- Streak
- Brown
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Monoclinic
- Crystal habit
- Anhedral grains
- Cleavage
- Good on {100}, one imperfect
- Rarity
- Rare
- Uses
- Collector
- Host rock
- pegmatite
Where rockhounds find radekškodaite-(la)
Classic worldwide localities
- Czech Republic
Field-hunting tip
Where it forms: pegmatite. If you start seeing fluorite, quartz, feldspar in float, you are in the right ground. Typical habit: anhedral grains. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify radekškodaite-(la)?+
Where is radekškodaite-(la) found?+
What rocks look like radekškodaite-(la)?+
What minerals are found with radekškodaite-(la)?+
What kind of rock does radekškodaite-(la) form in?+
What is radekškodaite-(la) used for?+
Find radekškodaite-(la) on the map
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