I do not even like that stone on a house and no it is not for a walkway IMO. Check with the stone company what they say about using that for a walkway.Not what your HOA thinks

It depends upon the properties of the stone. Have you asked Gallegos?

They can just stick the thicker stone down more into the ground. However, as Mark noted, what are the properties of the stone? Meaning, can this be used in an outdoor application rated for your area? Is this real stone or some concrete fake stuff? Where do you live? Is salt on the walkway going to be an issue? That sort of thing.

Stones that aren't dressed for walkways might be too uneven or too slippery.

A good stone mason can turn any stone into a walkway. Doesn't mean you can actually find one willing to do this, though! And it doesn't mean the stone will hold up the way you want it to even if you do get it in.

Some stones are very porous and will discolor or will wear down quickly, etc. Charming in the back garden, but less desirable in a more formal entry.

House ”siding” is (may) not be load bearing. It may be a manufactured product vs stone.

Thanks folks, and to answer some of the questions:

It is certainly genuine stone and about 6" thick. It's harder than sandstone but not as hard as granite.

This stone is rated for outside applications.

It should rarely be slippery on the front walk portion because there are snow-melting coils under the stone (so no shoveling and no snow buildup).

This is Colorado at 9400 ft elevation.

We need to care what the HOA thinks because they are a bit extreme for this development and any changes would cost us time and money.

I like to use stone on my projects that can be found in nature locally regardless of where it is processed.

6" stone is going to make the most stable solid walkway in your development. It's beyond adequate for vehicle traffic. If you're going to heat it for snow clearing, it's going to take a little longer. The guys laying it will know they've had a workout when the jobs done.

A nice touch would be to carry the same stone into the foyer, if possible, and stop at the header. It would help connect the inside with the outside.

Greetings from the Front Range. Love following your project. We just installed hydronic radiant heat under concrete and the tubing is only 2” under the top of slab. Would a snowmelt system will work when it’s 6” under a walkway? It would certainly take more energy to heat it. Maybe ask the designer of your snowmelt system. And wouldn’t 6” stone for walkway application be significantly more expensive than a thinner stone, especially if it’s a large square footage?

I think all we are doing is guessing the OP needs to talk to the mason doing the work and it is not that the stone can't live outside but is it the right choice for a walkwaymaybe it gets slippery when wet etc.

Good comments, all. I believe that we ought to:

a. ensure the stone is not so thick so that snow-melt doesn't work

b. ensure that stone not too bumpy so that it's a trip hazard, so use "real" flagstone

c. change to irregular flagstone so that any color mixing of 2 types of stones not so noticeable

I'm thinking we could use the buff colored one (San Miguel) stone in irregular shapes and then mix in some darker stone so it roughly matches the house siding stone. We'll have to put in for a DRB change but there's no choice. So the pic below sort of mocks it up.

The correct stone exists, it's not currently available. I have friend moving into his new build in Norway without the stone drive. Until that gets worked out he's having gravel delivered and distributed. As you get your pricing info together, gravel could be a placeholder until the correct stone at the right price can be installed.

"Where do you all think that rocks have lived for the last billion years while waiting to be made into patios?"

Protected under 100 feet of other rock and soil.