Stromatolite?

[mr fossil]

Hello

i found these on a island in the Red Sea.

the island is literally made of fossils(LITTERALLY) at the bottom of the island you can find corals you would usually find deeper in the sea and as you climb up the mountain you start seeing shallow water creatures like giant clams.

The island reaches 70 meters high and there are fossils up until the top. These fossils(in the pictures) could only be found on the top couple of meters

what could these be?

thank you for your time !

Edited January 28, 2022 by mr fossil

[laiosx]

layered calcite , most likely .

[abyssunder]

I thought they are close to shatter cones.

[mr fossil]

1 minute ago, abyssunder said:

I thought they are close to shatter cones.

Yes but the layers are horizontal not vertical. And how would a meteorite cause them in the sea?

[PaleoOrdo]

Difficult to see any clear fossile there, the rock is similar to one I found in Norway with more crystals (quartz or calcite?) than calsium carbonate. Like this rock (mine with more coarse crystals) with not well preserved fossiles, a brachiopod and a coral:

Edited January 28, 2022 by PaleoOrdo

[mr fossil]

1 minute ago, PaleoOrdo said:

Difficult to see any clear fossile there, the rock is similar to one I found in Norway with more crystals (quartz or calcite?) than kalsiumkarbonate. Like this rock (mine with more coarse crystals) with not well preserved fossiles, a barchipod and a coral:

Interesting 

cool fossil

[PaleoOrdo]

2 minutes ago, mr fossil said:

Interesting 

cool fossil

Yes, I like it even if not so well preserved. It was found in a place where is like a hill full of crystal rocks, I think it is silurian when the caledonian mountains emerged with bigger rivers full of crystal sediments.

[PaleoOrdo]

I wonder what is really the difference between calcite and quarts, seems OP is more full of calcite crystals, while mine is like "semi-quartz" enriched? If I am not wrong, some fossiles are pure quartz or coarse calcite?

[Kane]

29 minutes ago, PaleoOrdo said:

I wonder what is really the difference between calcite and quarts, 

Calcite: CaCO3
Quartz: SiO2

 

[Ludwigia]

This is a form of calcareous sinter similar to that which can be found in stalactites and stalagmites. Deposited continuously in very many thin concentric layers over time. In other words layered calcite with impurities.

[FranzBernhard]

You may try googling for 

"Erzbergit",

a more impure, but also finely layered calcium carbonate formation. Essentially a speleothem, formed in siderite rock - ankerite rock - limestone misch-masch.

Franz Bernhard

[PaleoOrdo]

2 hours ago, Kane said:

Calcite: CaCO3
Quartz: SiO2

I forgot "the hammer" when I philosophized. 

[PaleoOrdo]

1 hour ago, Ludwigia said:

Deposited continuously in very many thin concentric layers over time. In other words layered calcite with impurities.

I agree about OP. What about my rock, it is similar in apperance but has not layers. Is it a more coarse "not-layered calcite"? Here is another more close up photo of it:

[Ludwigia]

1 hour ago, PaleoOrdo said:

I agree about OP. What about my rock, it is similar in apperance but has not layers. Is it a more coarse "not-layered calcite"? Here is another more close up photo of it:

 

 

Limestone with amorphous calcite and calcitized brachiopods.

[abyssunder]

If it's calcite reacts with acid, if not it's quartz. Make the acid test with the powder of a tiny piece of the specimen (not the surrounding matrix). If it fizz it's calcite.

[PaleoOrdo]

2 hours ago, Ludwigia said:

Limestone with amorphous calcite and calcitized brachiopods.

Thanks a lot for the explanation!

 

22 minutes ago, abyssunder said:

If it's calcite reacts with acid, if not it's quartz. Make the acid test with the powder of a tiny piece of the specimen (not the surrounding matrix). If it fizz it's calcite.

Thanks a lot for the advice!