There are many names for materials, i.e. generic names, as well as brand names. It gets complicated when the same design of stone, may have more than one name. To keep the story short - basically, it's either NATURAL STONE, or MANMADE (aka PORCELAIN TILE). The former is literally stone, as in, you find the stone on the mountain, then use a big saw to cut it into a slab and put in your home, while the latter, is processed in factory using clay as a base, mixed around with other stone or resin material, baked like a cake in a huge ass oven, then labelled a brand name. It may, or may not be full-bodied.

If you refer to the word 'Quartz', this on its own, is a type of Natural Stone, like diamond, marble, granite, slate, limestone, etc. As for your 'Quartz Stone Tile', hmmm..... sounds like some fancy name for some kind of quartz-looking manmade tile.

As for 'joints', generally, most everything (in this context) has joints, including natural stones, depending on the size of the area it is applied onto and the design of the area, eg, counter top, floor, wall, etc. Joints just mean that each piece is not in its full single piece after application. Unless your pocket got no bottom, or that you are just using for a small table top, most applications of stones or tiles will have 'joints' at some point.