How to remove the circles of stain from the floor?

Hi,

We recently had a Travertine Floor laid to the downstairs of our home.  Travertine honed and filled. The floor has been sealed but needs a few more coates to finish it.

Yesterday some orange juice (concentraited) fell onto the floor which was wiped off

within 5 mins.  Last night however my husband and I noticed some circles of stain on the floor.  It could only be circles of splashes from the orange that fell but I dont understand how.  The colour of the stains are not orange in colour as you would think but a darker shade of the stone itself.  If they were not perfect (filled) circles that stood out I wouldnt worry but they do stand out and I need to get rid of them.  This has happened in two areas and affected possibly three slabs so apart from changeing them what can I do to remove them. 

 

 

 

Liana Gounaris
London.