Per promise to update edging drywall WALL - stone FLOOR Junction and filling floor crack with sanded caulking...
Color match is the most difficult. Doesn't take much shift to end up appearing 'highlighted' Functionally? Caulking tube works great! BUT! Out in a floor crack it shrinks like gang busters and have to apply more than three times to get level. And, if you overwork it, big mess, comes up as crumbs and rolls, and if try to overcome that you can make the surface look like you smoothed it with your finger losing all the 'sanded' texture, so does not match adjacent grout lines.
The original goal of doing the WALL-FLOOR junction with sanded caulking works great! Run a bead, let cure [several days], then CUT off excess and you end up with an impressively flat 'perfect' junction, yet the sanded texture of the top surface still remains. Just requires you to work a bit slowly using a sharp razor [I used a new blade for the box-cutter] to do the cuts flush with the floor. But with patience, very good looking.
Back to the crack running between the floor stones: After that diffiulty getting sanded caulking to finish nicely out in the floor area; tried using regular powder grout, comes in a bag from Home Depot, Polyblend Sanded Grout in Light Smoke. Best color match so far. After application, and gently wiping around to get off excess on top, let 'cure, or set up, or whatever for three to four days and 'test' by wiping a wet cloth over the junction/fill. CATASTROPHE!!! The stuff simply wipes out looking like a mud stripe on the paper towel. Even a dry finger will 'brush' the grout from between the stones!
Any ideas why the grout WON'T set up?