From the Wikipedia (after correcting two errors):
Yeşil Türbe (Green Tomb) is the mausoleum of the fifth Ottoman Sultan, Mehmed I, in Bursa, Turkey. It was built from 1414-1421, during his reign, together with the Yeşil Mosque opposite to it. Both buildings were designed by the same architect (Hacı Ivaz Pasha) and carried out by the same artisans.
It is built on a hexagonal plan and crowned with a hemi-spherical dome. The exterior of the mausoleum is clad with green-blue tiles that give it its name. A majority of the tiles were replaced by contemporary Kütahya tiles following damage in the Earthquake of Bursa 1855. The entry portal is crowned with semi-umbrella vault and has muqarnas niches above marble seats on both side of entrance. İznik tiles with flower patterns in blue, white and yellow adorn the portal.
Inside, past the carved wooden doors, the royal catafalque stands on a platform at the center surrounded by eight other tombs. It is richly decorated with scriptures and flower designs painted in yellow, white and blue glazed tiles. The lower section of walls is lined with blue-green tiles, also used in tympana of windows on the interior. The muqarnas niche of mihrab on the qibla wall is also set in a large frame of ornamental tilework: the mosaic of tiles inside the niche depicts a garden of roses, carnations and hyacinths. The chandelier and the colored glass windows are later additions.

I added older pictures, treated differently, so colour will vary. I think the 2014 pictures generally are more true, though the light was very mixed, lots of reflections in all sorts of colours playing havoc.