Ferro-pedrizite is a very rare member of the amphibole group, specifically within the sodium-rich subgroup. It is typically found as dark, prismatic crystals in highly evolved pegmatites and is prized primarily by advanced mineral collectors.
Is this ferro-pedrizite?
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 ferro-pedrizite with a known reference. Ferro-pedrizite sits at Mohs ~6, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: pale gray.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous.
- 4Match the color rangeCompare against the expected color range: dark gray-blue, violet-blue.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: prismatic crystals.
Often confused with
Ferro-pedrizite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Streak differs, so Ferro-pedrizite leaves pale gray, Arfvedsonite leaves deep bluish gray, gray-green.
How to tell apart: Streak differs, so Ferro-pedrizite leaves pale gray, Glaucophane leaves blue-gray.
How to tell apart: Streak differs, so Ferro-pedrizite leaves pale gray, Riebeckite leaves greenish brown.
Often found alongside ferro-pedrizite
Minerals reported to co-occur with ferro-pedrizite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- NaLi₂(Fe₂Al₂Li)Si₈O₂₂(OH)₂
- Mohs hardness
- ~6
- Density
- 3.13-3.16 g/cm³
- Colors
- Dark gray-blueViolet-blue
- Streak
- Pale gray
- Luster
- Vitreous
- Transparency
- Transparent
- Crystal system
- Monoclinic
- Crystal habit
- Prismatic crystals
- Cleavage
- Perfect in two directions
- Rarity
- Rare
- Uses
- Collector
- Host rock
- In veinlets associated with the metasomatism of spodumene-microcline pegmatite hosted by marble
Where rockhounds find ferro-pedrizite
Classic worldwide localities
- Sutlug pegmatite, Targi River Basin, Tyva Republic, Eastern Siberia, Russia
Field-hunting tip
Where it forms: In veinlets associated with the metasomatism of spodumene-microcline pegmatite hosted by marble. If you start seeing quartz, albite, microcline in float, you are in the right ground. Typical habit: prismatic crystals. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify ferro-pedrizite?+
Where is ferro-pedrizite found?+
What rocks look like ferro-pedrizite?+
What minerals are found with ferro-pedrizite?+
What kind of rock does ferro-pedrizite form in?+
What is ferro-pedrizite used for?+
Find ferro-pedrizite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
