Now I can't "not" see that...Thanks a lot. It makes ignoring the dictator in front of them easier though.

Where the veins in each tile are aligned to make it all look like one continuous piece, or a solid slab. Or the face of the rock mined at the quarry.
On larger projects the pieces are marked at the quarry then laid so the veins are continuous. Most State Capitol buildings have great examples of this craft. I learned about it working during the restoration project at the CA state capitol which has miles of incredible bookmarked marble panels.

...find some visuals?

The tiles behind the fool. See how the veins are all Willy nilly. They should be a pattern.

http://www.cnn.com/2017/09/18/politics/donald-trump-un-speech-iran-north-korea/index.html

erratic and messy, like the fool in front of them..

My husband second step grandfather was a marble importer. When the Florida state capital building was remodeled in 1952 he supplied the marble for the building. In the late 1970s when the building was restored to the 1902 version, we bought as much of the marble from the state surplus sale as we could. When we built our house ten years ago we finally used the marble that we had purchased.

Most is Georgia white marble - some was paneling along the halls but some sheets had been the dividing walls in the rest rooms. The sheets were used above our kitchen counters and as the seat in the shower in the master bath.

A very few pieces of the green marble that had been used as base boards survived - those were used as a short back splash in the half bath.

"Uncle Billy" as my husband called his step grandfather, hated the green marble. His sources in Italy did not have good quality and the stuff tended to crumble.

Takes special setting materials so they don't warp when they get wet. Yeah that Georgia marble was widely used before all the imports took over.

It isn't used very much so the marble stays dry most of the time.

The idiot that did our floors - wood and tile - and the stone and tile for the back splashes and counters was terrible. In our old mobile home I tiled the master bath and the counters in the kitchen. Even when the house was moved, nothing cracked or came loose.

One the other hand, in this house that is only ten years old, with tile on a slab floor tiles are coming loose and cracking. I also hate the way he spaced the tiles - he didn't center them, just started with full tiles on one side and let the other side be small slices. I argued with him, but he refused to listen. By the time we were done, I just wanted all the idiots OUT of my house and be done with them.

Some day I will get the tiles reseated and some of the areas regrouted so they look better. Some other decade...

I've heard it both ways.

If they aren't going to take the time to bookmatch the marble, they should have just used granite or some other stone without veins.

To deliberately mount the tiles so they did not appear as if they were of one slab?

Read the article about TRump not liking them, they were redone in the 80s which covers my time in the business.