Glossopteris with algae ?

[Yoda]

I recently aquired this Glossopteris. 
It has a green coating which looks like algae. 
 

How do I remove this without damaging the fossil ?

 

 

[Fossildude19]

I would try soapy water and a "soft" toothbrush, myself. 

Test a small area in the lower right corner to see if it works. 

 

[dsalles]

I would try diluted Clorox. First on the back, of course. And be careful.

[Yoda]

3 hours ago, Fossildude19 said:

I would try soapy water and a "soft" toothbrush, myself. 

Test a small area in the lower right corner to see if it works. 

 

Thanks. 
I think I will give this a go first 
and if it doesn’t work, will give this second idea a go:

 

1 hour ago, dsalles said:

I would try diluted Clorox. First on the back, of course. And be careful.

 

[Fossildude19]

Let us know your results.   

[Yoda]

1 hour ago, Fossildude19 said:

Let us know your results.   

Will do 

 

Am planning on attending to this over the weekend. 

[Yoda]

So I didn’t have a spare toothbrush. 
What I did was use a cotton wool earbud dipped in warm soapy water. And very gently rubbed over the green bits. 
Not perfect, but a lot better.