Marble cannot be cleaned with any typical bathroom cleaning products - only pH neutral. i personally wouldn't use marble on my bathroom floor.

Penny rounds! The basketweave may be too much considering the main floor is herringbone

Polished pennyrounds probably aren't too bad for slippage due to all the grout. I have ceramic pennyround in my shower. The tiles themselves are very glossy but the floor isn't slippery. My pennyround tile is a bit rounded I think so that the floor isn't absolutely flat, but slightly bumpy. I'm not sure I'm explaining this very well. I have weird, sensitive feet and I find it a tad uncomfortable, as I would with the pebble tile. I think the marble pennyrounds look flat.

I know there is a theory that grout reduces the sillage of mosaics but I don't really find that to be true. I have small hex tile on my bathroom floor that is impossibly slippery despite loads of grout lines. Look for the COF rating on any tile you intend to use on a shower or bathroom floor.

Herringbone and basket weave sounds just as busy as herring bone and penny rounds if that is one concern you are weighing.

Not sure if mosaic tiles have manufacturer Coefficient Of Friction (DCOF) slip test results. All the larger scale tile I put on my bathroom floors I made sure the COF was checked. Polished stone is like ice when wet but lots of grout may make the difference. As for the large scale polished tile you are considering just make sure you file an end of life directive before your first shower.

Both are nice tile styles. I think the question is, What does the rest of your house look like?

If it's casual, a bit country or cottage and cute -- go with those penny rounds.

On the other hand, if it's a bit more elegant and traditional -- basketweave all the way.

Thanks for all your comments! So helpful! What should the COF rating be for bathroom floor tiles so they are not too slippery? Thanks!

I have polished marble basket weave tiles on my bathroom and shower floor and they are etirely non-skid because of the grout.

Completely different than a place I was renting which had 12" x 12" tiles which were a death hazard if my feet were even slightly damp.

Sounds like polished 6x18 herringbone on the main bath floor could be super slippery? I don’t see the COF rating for the nanoglass.

The basketweave for the shower floor probably is more elegant and traditional for the primary bath which would work well but don’t want it to be too much or too busy with the herringbone on the main bath floor.

Realized that marble will eventually etch and will be more noticeable on polished than on honed marble.

I like penny rounds in the shower with herringbone for the main floor, because a guide of combining multiple patterns is to combine curves with straight lines. To address you COF question, read the following article but I think the quick answer may be 0.42 or higher. https://www.thespruce.com/coefficient-of-friction-specs-to-buy-best-1822608

I ditto the advice to NOT use marble on your shower floor. Our honed marble floor has been a nightmare to clean. It has etched, the grout has deteriorated, and I am up for a remodel of the bathroom as a result. Go for marble look porcelain. NOT marble. Especially not honed marble which will capture all kinds of icky stuff that you will have a horrible time trying to remove.

Oh no about marble mosaics on the shower floor as far as cleaning!

I love penny rounds because their simple shape can go in either a more modern or more classic direction. That would be my pick.

I echo @David Cary. My HUGE bathroom remodel regret is using hex tiles (not marble). What a PITA to clean! Now, several years in, the grout is stained beyond repair and the tile never looks clean. Never again. If you decide to go ahead with it, consider using a darker grout color.

I like both and the penny rounds would be nice to add curves. But do penny rounds seem more juvenile? Like for a kids bath? Or for a laundry room? Penny rounds seem elegant for a primary bath?

I don't think marble tile reads "juvenile". But if it bugs you, you could go with 1" marble hexes instead, which would give it a more art deco look. Here's a photo of a primary bath floor we did for a recent client with marble hexes:

Beauty and the Baths: Primary Bath · More Info

Beauty and the Baths: Primary Bath · More Info

@David Cary Speaking of pink mildew... you don't happen to use Method Daily Shower Spray do you? Its amazing at keeping the shower glass clean without squeegeeing it but the growth of this pink mold/mildew is not something I think I've ever really seen before. My thought is that the spray makes it flourish.

Note to self.... PINK BATHROOM next time around!

Good suggestion to go with a hex but unfortunately this marble only comes in a basketweave or penny round mosaic. Of course could pick a different tile for the shower floor but since we already have another tile on the main bath floor, don’t want too many different kinds of tile and the main bath floor tile has a 2x2 square mosaic tile which I do not care for.

by the way, so neat how the marble hex goes from the main bath floor to the shower floor!

To clarify, the same marble comes in an elongated hex but not sure elongated hex would look as good as regular hex

@m111675 I just put in a bathroom floor that went into the shower. The entire floor is heated, even the shower. Electric radiant heat feel so yummy. Surprise! It dries the floor, grout and all. I'm not wanting to contradict anyone. I'm just saying, if you haven't considered it, please do.

@Paul F I experienced pink/orange mold once and read it was due to outside air. I told dear hubby that he had to shut the bathroom door if he opened the sliders off the bedroom. Problem solved. That may not be your situation though.

@K L Two seperate systems, right? One for in the shower and one for out?

Showers require proper maintenance. MANY things can contribute to build up whether it's actually mold or mildew, or simply discoloration. While we have some opinions on this, we will limit our comments to what we believe are the most important considerations in your material selections and have not been discussed here. While marble has been used for centuries in wet areas, two primary considerations: The qualifications and experience of the installer (proper prep for a marble shower), and the quality of the marble product. OK, three: Your tolerance for proper maintenance. It appears you may be ordering your marble tile online? There is no country of origin noted (not where it ships from, but where it was mined). There is often a correlation between price and quality. Some of the lower priced marble we see today is mined in China (but perhaps shipped to another country for distribution, like Vietnam, etc.). We would not install your product before we inspected it. With decades of experience, we can tell quickly if this stone is appropriate for a shower. Some of these cheaper marbles are very porous, soft bodied (chaulky). They will literally crumble under our saws when we cut them. We can hold them up to light, knock on them, and use other methods to assess how soft or porous the material is. Further, ordering what should be a premium product online, comes with the other issues, like the variances in shade. All natural stone will have color/shade variance. The less expensive is likely to have even more. What will you do if your order arrives with extreme variances? Are you prepared for that? We would reject any product if we could not confirm it's suitablity and longevity for the application. That brings us to the quality and experience of your installer. Hopefully you have engaged them in your selection process and they have reviewed and personally handled the material and approved it. (Don't blame them down the road if they were not involved). If they have limited experience with marble shower installations or cannot answer your questions, you need to choose a different product or different installer. Either smaller mosaic pattern you're considering works and would offer the slip resistance needed. Grout has come a long way and the proper premium grout for the application will provide better stain resistance compared to years ago. Again, a qualified installer will know and use the best products. Start there. Our two cents and good luck with your project.

@Paul F. no it's one system. Warmly Yours is the company name. Good technical support. I love that the entire bathroom is warm. I don't have any glass door or shower curtain at the shower entry and no threshold either. I was a little worried I would feel chilled but I don't. And I think it's because of the floor. I didn't get everything right with the baty, but I sure am glad I heated the floor. Here is the view from the door. It's a little different.

Interesting. We started using Method daily shower spray to deal with the pink mildew. We don't have much glass - only above 4 ft. So keeping glass clean isn't an issue - on purpose. We are doorless also.

So the Method hasn't seemed to make it worse but not sure it makes it much better. We have committed to finishing the massive container we bought but won't buy more.

To clarify, we lived here for 3.5 years and just started using the Method so that wasn't the cause.

I have to discount a professional designer that doesn't live with the product on a daily basis. Now, it they do, then great. Have them explain their cleaning regimen and grout longevity. And if it sounds acceptable to you, then go with it. And I am sure some of this is local - whether water quality or background humidity.

Luxury shouldn't be a big PITA. And in so many others it isn't - in fact it is less maintenance - stone patio vs deck, brick vs siding etc.

A pH neutral stone cleaner, microfiber cloth, and a soft long handled brush handles most cleaning just fine. https://www.lowes.com/pd/Zep-Neutral-Ph-Floor-Cleaner-128-fl-oz-Pour-Bottle-Liquid-Floor-Cleaner/3621314

@KL, the bath I posted above also has radiant heat floor throughout, including the shower. It's a really nice feature if you plan for it in advance.

Method shower spray has absolutely no effect on the pink "mold"... which is surprising considering it is for cleaning a shower on a daily basis. "Pink mold is a misleading name, because it is actually a bacteria called Serratia marcescens. It can range in color from pink to red or orange. It is normally seen growing on shower grout, or around the drain of sinks with a slimy or fuzzy appearance. Serratia marcescens is a very common bacteria that eats fat or phosphorus- containing substances. A small colony of pink mold will not normally be a health threat, but if it gets big enough it can be a problem for some people. It can cause urinary tract infections, blood poisoning, pneumonia or gastrointestinal problems. If Serratia marcescens is able to enter an open wound, it can cause an infection that may require antibiotics."

Thanks for the reminder about the bacteria - I had researched this before and I knew it wasn't really mold. I have to say that part of our issue is the local water supply. We have more pink in various places (ie toilet bowls) than our last several houses just next town over - but with different water source. Good to know Method doesn't do anything - that was my impression anyway. Explains why bleach works well (which interestingly is used by someone nearby but different water source).

I've just committed to better cleaning practices which would be a whole lot easier with few grout lines but really solid surface would be ideal. And as a reply to tile pro earlier - we used the latest greatest commercial style grout - at least that is what we were told and it was way more expensive than regular grout (but worth it). This isn't a spec or tract build and I am pretty sure that I personally saw the grout bags at the time.

Isn't it really a bad idea that we put all these grooves in a floor that gets wet often? And then a worse idea that it is porous. Does it really matter if it is a bacteria or a mold that likes to grow there? Sometimes taste trends toward expensive things that are hard to maintain because they remain rare - reinforcing that it is a luxury item. Jumping off soapbox....