Restoring quarry tiles

I've got some fabulous quarry tiles underneath some lino. It looks like they've got cement over them about a 1mm thick layer. How should I restore them?

A response from one of our very best tradespeople:

"If it is cement then try using an acid based brick cleaner in a small area as a test first.  Then you could seal the tiles with linseed oil which takes time as you will need to build up the coats.  Try to apply one coat a week then one a month etc until you reach your desired effect.  There are plenty of sealers on the market today which may also be of use."

Graham Honeyball, Premier Tiling Ltd.
Graham likes to think of Premier Tiling Ltd. as a company that is approachable and friendly as he's always happy to answer questions or give advice. As a company, they carry out all aspects of wall and floor tiling and install under-tile heating systems. They also cover off the installation and care of Victorian period floors. Graham loves Victorian floors and bringing them back to life for future generations to enjoy.