The traditional mosaic tile rosette uses end grain and can be elegant, precise, tasteful or even blocky and simple.  What it can never be is bright with shiny white (or other light colours).  The open grain of the wood makes the whites darker.  End grain is used so that you can make up long “logs” and slice many tiles off.  It is also easier and cleaner to plane, scrape and cut the wood or veneer along the grain as you prepare the mosaic logs.  So if you want a bright white what can you do?  Obviously the answer is to change the orientation and use side grain.  This rosette is not a traditional mosaic but uses a combination of side and end grain to beautiful result.  The side grain retains the colour of the wood and the end grain is darker (here largely due to the glue but later due to the varnish).