Blueish rock what is it ?

[LONEWOLF]

Ok... Well then does the Blue/Black areas Crumble away like the Limestone material does? and more easily after you have washed it? This is Fun...

LW...

 

[Wishfull]

Ok... Well then does the Blue/Black areas Crumble away like the Limestone material does? and more easily after you have washed it? This is Fun...

LW...

No. The blue stuff is hard and heavy.

 

[Heatho]

I'm thinking possibly hematite or limonite. Looks like some type of mineral with a high iron content.

 

[shivan]

Hardness test, streak test and specific gravity test will give you a lot better idea of what it is.

 

[Wishfull]

Scratched it on back of a porcelain tile and it was dark brown. If that helps at all.

 

[casper]

I'm not a geologist but what came to my mind was that it looks like photos I've seen of contact zone metamorphism of the country rock :/

 

[Goldpick]

Same as Heatho, thought the streak should be on the red end of the scale of brown - could also be down to other impurities in the rock. Also appears to be some irridecent coating on parts of the rock, may well be a hydrothermal sourced hematite - think they list the coating as an aluminium/phosphate combination.

 

[LONEWOLF]

Here is a Guide to your Streak Test....

http://geology.com/minerals/streak-test.shtml

https://www.thoughtco.com/mineral-streak-examples-4122988

The Second Link has pictures of Minerals Streak... :Y:

LW...

 

[LONEWOLF]

Any ideas yet Wishfull?.... ]

LW...

 

[Wishfull]

Welll... it's got a dark brown to black streak. Chromite has that colour streak. It's not magnetic.

Sg test may be next.

 

[XIV]

Looks like manganese bud.
I'll find a photo of some I have at home.
Give me a few minutes.

 

[XIV]

If you rub it with your finger, it should leave a faint streak on your finger. Bit like a gray lead would.

 

[LONEWOLF]

Chromite was 'One' of my Choices as I saw a couple of pics on another site VERY similar to yours... I Kept getting a different streaks on the Tiles I have here, so I got some proper Streak Plates from Ebay for a few $$.. Better results now... :Y:

LW...

 

[SWright]

G'Day All

Brown steak means its limonite or haematite, a black streak would be manganese - pyrolucite

Araluen

 

[LONEWOLF]

Ok, So what would be a Brownish-Blackish Streak ?

LW...

 

[Wishfull]

I'm thinking possibly hematite or limonite. Looks like some type of mineral with a high iron content.

Guess what. My retired geologist friend says the rock is definitely Limonite.Well done Heatho :Y:

 

[LONEWOLF]

Well there you go ... Limonite it is.... :Y:

LW...

 

[Heatho]

I'm thinking possibly hematite or limonite. Looks like some type of mineral with a high iron content.

Guess what. My retired geologist friend says the rock is definitely Limonite.Well done Heatho :Y:

Cheers mate, after you cleaned it the oxides were a dead give away, also the streak test was a dead give away too. Have seen plenty of the stuff while gem fossicking.

 

[jethro]

Hmm. That proves me wrong. I was gonna say petrified Teradactil turd

 

[LONEWOLF]

Any New rocks to Tumble Wishfull?...

LW....