Dredged this up! Any Ideas

[jog]

Found this in my pan after dredging. I was in a creek in Northwest Oregon. Have looked in my Gem book but can't find anything like this.

 

[strickman]

they should polish well. but i would not polish one with a good natural cut . it takes a long time to tumble. i haven't tumbled much. i have cabbed ,and cut with a dremel and a diamond cutting wheel. wish i had the equip.to facet . that is a definite art form. out of my league .i make my own pendants [gold] wish i could facet as well.

 

[jog]

they should polish well. but i would not polish one with a good natural cut . it takes a long time to tumble. i haven't tumbled much. i have cabbed ,and cut with a dremel and a diamond cutting wheel. wish i had the equip.to facet . that is a definite art form. out of my league .i make my own pendants [gold] wish i could facet as well.

We just came back from a Gem and bead show today. If you were to hit some of these shows and start, I would bet you could pick it up pretty quick. They do make some hand tools so you could make one or two just to see how it goes. A person can spend a ton of money real fast on facet equipment.

 

[Eu_citzen]

OK! I just tried scratching a piece of glass and it will do it with very little effort. Does that help?

So the rock does scratch glass? Good.
That rules out Xenotime-(Y)

Does Quartz scratch it?
If so I'd think Vesuvianite.
http://www.mindat.org/photo-211813.html

If not, I'm still thinking Zircon.

i'm no geologist ,don't claim to be .could be something else .maybe even tourmaline ,don't know. but i do know i have found some odd garnets ,as well as other oddities.and they are not always typical . maybe even the result of twinning. or cleaving. but they are cool. i need to separate some more ,i have pounds of them .

Neither am I. I'm just a student to mineralogy and Gemmology.
But happen to be interested in geology to.
Garnets can have pretty odd shapes, but not a tetragonal bi pyramidal shape.
(unless it replaced a earlier mineral, and if it did we would not see any cleaving of the tips of the pyramids)

 

[jog]

Tried to scratch it with a piece of quartz, just left a mark but didn't appear to really scratch it.

 

[Tuberale]

Garnet should be much harder than quartz, so shouldn't have had any effect.

 

[Eu_citzen]

Garnet should be much harder than quartz, so shouldn't have had any effect.

Ehh??
Garnet is either just softer then Quartz or just harder. NOT much harder.
The hardest Garnets (e.g. Spessartine http://webmineral.com/data/Spessartine.shtml) reach a max hardness of 7.5 on the Mohs scale.
Quartz is at 7.

Zircon is also up at 7.5 with the hardest Garnets.

 

[jog]

Had a sample into a Jeweler slash rock guy who specializes in Oregon coastal rocks and Gems and he thinks it could be Argonite. Hardness is 7-8.

 

[Eu_citzen]

Had a sample into a Jeweler slash rock guy who specializes in Oregon coastal rocks and Gems and he thinks it could be Argonite. Hardness is 7-8.

Argonite? Not Aragonite?
Argonite is a gas mixture.

Aragonite has a hardness of around 3½ to 4.
Not fitting, either I think.
Although it can look very similar.