That second picture is of a table with breadboard ends. Properly done, breadboard ends take a lot of machining, since the addition is done by means of a long mortise and tenon, with the end pinned to the body to allow for wood movement. That movement will happen because the grain directions are 90° in orientation, meaning the movements(natural and unstoppable) are in different directions.

So, if you have access to a woodworker with the necessary tools and skills, yes, it can be done. It is a huge difference from simply gluing pieces on each end---which will fail.

It will look different. How well it looks has a lot to do with what pieces are used and how they are finished.

Thank you HandyMac, I was wondering if the added pieces added to the ends would be glued or doweled or what, to secure them. I understand your comments re the breadboard ends and I was unintentionally misleading in adding that photo....I would want a glued or other method that's strong, long lasting and as seamless as possible. It sounds as though you were cautioning me about the fragility of my ends if I go to glue. I do appreciate your input.

A glue joint like you envision will fail. Only question is when. Reason is because wood moves due to moisture/temperature changes. You cannot stop this movement. Since the wood moves, is has to be joined to allow that movement. Gluing wood together with the grain aligned(matching) allows the movement, since the grains are matched.

Gluing with grain pattern at 90° angles means the movement will be different---and the joint will fail. That is the reason for the technique I described. The joint is tight where the two pieces are joined, but there is space to allow for the movement. That is the way very well built and expensive furniture is made. Because it is the only way to assure the joint lasts.

Those leftover pieces are pretty scrappy. It doesn't look like you have much to work with there.

Thank you Naturalist~ this process of finishing my slab has been long! I agree that the slab should not be added on to.

It is now finished with several coats of Polyurethane. It still needs legs and I found someone who can combine my leftover Black Acacia pieces with metal to create the X style legs I would like. We'll see! I've attached recent photos of the finish as it sits on a plastic 48" long table. The slab is now in the hands of a wood/metal worker.