Opalised fossil or opalised mineral?

[Vopros]

This is a boulder opal with some kind of crystals in it. It was sold as “vegetation fossil”.

I am attaching a few images that were taken under a microscope. The dimension of the opal is

15.4 x 9 x 4.9mm

And the crystals, or whatever it is, take around 1/3 of the length. 
So, is this a fossil and a fossil of what or these are some minerals?

Thanks.

[Vopros]

Here are a few more pictures

[JBkansas]

Where is it from?

[Vopros]

1 minute ago, JBkansas said:

Where is it from?

It is from from Jundah, Queensland, Australia and here is the video

 

[Ludwigia]

I would hazard the guess that those are pseudomorphized minerals, but I coudn't say which. I'm not seeing anything fossiliferous at any rate.

[JBkansas]

12 hours ago, Vopros said:

This view has a bit of a stromatolite look but that seems unlikely given the crystal structures on the other faces.

[Vopros]

5 hours ago, Ludwigia said:

I would hazard the guess that those are pseudomorphized minerals, but I coudn't say which. I'm not seeing anything fossiliferous at any rate.

It is possible but then it is a question how it formed. I have heard only about one type of pseudomorphs in Australia opals, and it is a so-called pineapple.  However, I have never heard about some kind of crystals inside an opal. Have you?

Thank you.

[Ludwigia]

Like I said in other words, I'm seeing a mineral or minerals which has or have been transformed into opal.

[rocket]

looks a bit like a part of a pineapple-opal

[Vopros]

Ok, I have done some more work and now I believe this opal contains a few tiny cycad cones,  some of which produced leaves.

First notice the structure I circled. See all these small triangles.

Now compare two images from the second picture. The upper image my old opal cycad. The lower image my new opal 

See the similarity in the shapes between the right-hand sides of both images?

it cannot be a coincidence. 

[Ludwigia]

You sound pretty convinced now, and I would grant that it's a good possibility. Why don't you take it to an expert at a natural history museum or university department for confirmation?

[Vopros]

4 hours ago, Ludwigia said:

You sound pretty convinced now, and I would grant that it's a good possibility. Why don't you take it to an expert at a natural history museum or university department for confirmation?

Thank you! I will try to take it to an expert.

[rodrex]

I have seen pinecones in cross section, but agree that this looks like a mineral pseudomorph.