The SGPC, after they demolished all the beautiful historic bungaay (which we commemorate in our ardaas every day, in a sick twist of irony, praying that they stand for all time - "Chounkiya Chandae Bungaay jugo jug atal") scattered around the sarovar in order to widen the parikrama. Visitors to the city of Amritsar noted that these bungaay were among the very best representations of Sikh art and architecture, their edifices covered with murals and intricate engravings.
There is no meaning behind these tiles other than the willful destruction of our history for the sake of 'beautification' and greed (maintaining the artwork of the bungaay would have cost the SGPC a lot of cash). The Gurdwara management of Takhat Sri Hazur Sahib did the same thing, destroying the historic Bunga of the Ramgharia Misl, among other things, so that they could carpet bomb the place with marble.
This trend is repeating itself in countless historic Guru Ghars. Several of the mango trees at Gurdwara Amb Sahib, dating back to Guru Gobind Singh's time, were also chopped down to accommodate new marble tiling, and others strangled to death by all the stone.
These revolting men have no respect for Sikh Itihaas.