In the winter, glue may take 36 hours to set. In a dry day of summer. it may take 2 hours.
You have to wait until the glue that holds a tessera to its support is set before you can glue another one beside it. UNLESS, something else already holds that tessera... Which could be either an other tessera, or a whole line of them...
It sounds stupid but it is not. If, for example, you have one stable row of tesserae solidly glued to its support, you can use it to hold several parallel rows of tessera. This then allows you to work faster.
So at the beginning of a project, I lay long lines of tessera, each line of the same color and I let them dry up. Then I use these original rows as bases to build up wider area. As I have built several lines, I can simultaneously work on several areas of my mosaic and progress faster.
This why I always begin with the outer contour of a project.
A long row of black granite is now separating the face from the veils. It does not look black but grey because you only see the unpolished back of the stone. (The shiny black face is glued to the support)
I also started the sanded area on the side. Please remember that one is the mirror image of the other. Mariam has the sand to her Right and Mariam's sister has it to her Left...
This sanded area is made of 3 different stones : Gold Travertine, Beige Travertine and Crema Marble.
After 15 hours of work, 5 different materials are involved on the bench:
Many more will follow !