Abenakiite-(Ce) is a rare sodium-cerium silicate found almost exclusively in the alkaline igneous rocks of Mont Saint-Hilaire. It typically occurs as small, unremarkable yellow-brown grains embedded in sodalite-rich syenite xenoliths. Due to its radioactive content and extreme rarity, it is highly sought after by advanced collectors of alkaline complex minerals.

Hardness

Mohs

Luster

Greasy

Streak

White

Transparency

Translucent

mineralrare

Abenakiite-(Ce)

Hardness: 4
Luster: Greasy
Streak: White
Transparency: Translucent

Is this abenakiite-(ce)?

5-step field check

Run through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.

1
Test the hardness
Try to scratch abenakiite-(ce) with a known reference. Abenakiite-(Ce) sits at Mohs 4, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Abenakiite-(Ce) leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Abenakiite-(Ce) typically shows a greasy luster.
4
Match the color range
Compare against the expected color range: yellow, brown, yellow-brown.
5
Look at form & habit
Crystal system: trigonal. Typical habit: anhedral grains, granular masses.

Often confused with

Abenakiite-(Ce) vs. its common look-alikes, and how to tell them apart in the field.

mineral

Eudialyte

Mohs 5-6

How to tell apart: Eudialyte is the harder of the two (Mohs 5-6 vs. 4); luster reads greasy on Abenakiite-(Ce) and vitreous on Eudialyte.

How to tell apart: Sodalite is the harder of the two (Mohs 5.5-6 vs. 4); luster reads greasy on Abenakiite-(Ce) and vitreous on Sodalite.

Compare →

Often found alongside abenakiite-(ce)

Minerals reported to co-occur with abenakiite-(ce). Spotting these in float or country rock is a strong cue you are in the right ground.

All properties

Chemical formula: Na₂₆Ce₆(SiO₃)₆(PO₄)₆(CO₃)₆(SO₂)O
Mohs hardness: 4
Colors: Yellow Brown Yellow-brown
Streak: White
Luster: Greasy
Transparency: Translucent
Crystal system: Trigonal
Crystal habit: Anhedral Grains, Granular Masses
Cleavage: None Observed
Rarity: Rare
Uses: Collector
Host rock: Alkaline Igneous Complexes

Where rockhounds find abenakiite-(ce)

Classic worldwide localities

Mont Saint-Hilaire, Quebec, Canada

Field-hunting tip

Look in alkaline igneous complexes country, the host setting where abenakiite-(ce) typically forms. If you start seeing aegirine, microcline, nepheline in float, you are in the right ground. Field specimens usually show a anhedral grains, granular masses habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify abenakiite-(ce)?+

Mohs hardness is 4. It typically shows a greasy luster. The streak is white. Common colors include yellow, brown, yellow-brown.

Where is abenakiite-(ce) found?+

Notable localities include Mont Saint-Hilaire, Quebec, Canada.

Is abenakiite-(ce) safe to handle?+

This mineral is radioactive. Contains thorium and rare earth elements; handle with care and wash hands thoroughly after handling. Should be stored in a labeled, contained environment to avoid inhalation or ingestion of dust. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like abenakiite-(ce)?+

Abenakiite-(Ce) is most often confused with Eudialyte, Sodalite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with abenakiite-(ce)?+

Abenakiite-(Ce) commonly co-occurs with Aegirine, Microcline, Nepheline, Analcime, Eudialyte. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does abenakiite-(ce) form in?+

Abenakiite-(Ce) typically forms in alkaline igneous complexes. Working float back to the host body is the standard way to chase a fresh occurrence.

What is abenakiite-(ce) used for?+

Abenakiite-(Ce) is used in collector.

Find abenakiite-(ce) on the map

RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.