Hastingsite is a dark-colored member of the calcic amphibole group often found in alkaline igneous environments. Collectors look for its characteristic prismatic, black-to-brownish crystals, which are visually indistinguishable from other common amphiboles without chemical analysis. It is most frequently encountered in specimens from syenite or nepheline syenite localities.
Is this hastingsite?
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 hastingsite with a known reference. Hastingsite sits at Mohs 5-6, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Hastingsite leaves a white to light gray streak.
- 3Read the lusterHold the specimen under a strong light. Hastingsite typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: black, dark green, dark brown.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: prismatic, massive, granular.
Often confused with
Hastingsite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Streak differs, so Hastingsite leaves white to light gray, Hornblende leaves grayish-white.
How to tell apart: Streak differs, so Hastingsite leaves white to light gray, Pargasite leaves white.
How to tell apart: Streak differs, so Hastingsite leaves white to light gray, Ferro-edenite leaves white.
Often found alongside hastingsite
Minerals reported to co-occur with hastingsite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- NaCa₂Fe₄Fe³⁺(Si₆Al₂)O₂₂(OH)₂
- Mohs hardness
- 5-6
- Density
- 3.4-3.5 g/cm³
- Streak
- White to Light Gray
- Luster
- Vitreous
- Transparency
- Opaque
- Crystal system
- Monoclinic
- Crystal habit
- Prismatic, Massive, Granular
- Cleavage
- Perfect in Two Directions
- Rarity
- Uncommon
- Uses
- Collector
- Host rock
- Alkaline Igneous Rocks, Syenites, Nepheline Syenites
- Typical price
- $10-60 for small mineral specimens
Where rockhounds find hastingsite
Classic worldwide localities
- Hastings County, Ontario, Canada
- Litchfield, Maine, USA
- Kola Peninsula, Russia
- Fen Complex, Norway
Field-hunting tip
Look in alkaline igneous rocks, syenites, nepheline syenites country, the host setting where hastingsite typically forms. If you start seeing nepheline, microcline, aegirine in float, you are in the right ground. Field specimens usually show a prismatic, massive, granular habit, so train your eye for that shape before scanning the outcrop.
Common questions
How do you identify hastingsite?+
Where is hastingsite found?+
How much is hastingsite worth?+
What rocks look like hastingsite?+
What minerals are found with hastingsite?+
What kind of rock does hastingsite form in?+
What is hastingsite used for?+
Find hastingsite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
