Yes - episode 1226 is the one - thanks CRL - it indicates Richard talking about countertops and I even went to the website of the provider of the marble countertop but I don't see any information there on the "factory sealed" heat process.
FYI - The episode showed a video of a marble slab being sealed - and I can't remember it all but it was not just a "wipe on some type of sealant" process. They had a big table where the slab rolled back and forth, etc. Strange that there is nothing on the web. I would really like to know more. Especially given the claims that were made.

I saw that one yesterday. I didn't think get the feeling that it would be an inexpensive option. She had a small kitchen, and was installing flat-pack cabinets which would save her money. But she was also getting marble, which would either indicate that her budget wasn't that tight, or she had saved enough through other choices to be able to splurge.

They also said the finish would last "a long time", but didn't indicate whether that meant, like, 25 years? Or 2 years?

But I get the feeling this is something either your stone yard offers, or they don't. The equipment wasn't small or cheap looking. So, there might be more info on the TOH website, or you might just have to call your local yards to ask about it.

And I believe it's "Trethewey". I knew someone in high school with a similar name.

i saw it as well, and he did mention that it would prevent staining but not etching, in which case it's still just sealant, although he indicated it would last longer if factory applied. the stone will still patinate over time.

I saw this episode too, and was wondering about the process. I noticed she chose a polished finish, and I would only have chosen a matte finish for that beautiful marble. As EAM44 said, the process will prevent staining, not etching, and the polished finish will show etching more.

Having said that, I loved the comment from the professional chef Michael Symon. This same episode showed his home kitchen space that was empty and mocked-up with his planned cabinets and layout. He is installing Carrera marble in his kitchen (and a 60" Bluestar range BTW). He said he loved the lived-in look of marble he saw in kitchens in Italy with stains and marks and chips, and welcomed them for the marble in his own home. Great point of view!

As to the comments about the homeowner's kitchen budget in this episode - I would bet she received a discount on the marble because the fabricator will get its name on the show which is fantastic advertising.

Nothing to add about the factory sealed marble, but I do know that there is no discount given for being on the show....

Ajc71 - how do you know that no discount is given? I had heard a discount was possible for Ask This Old House episodes.