No. The “veins” in the white half are actual color swirls in the acrylic sheet. The reason they line up nicely with the flow of the leaf is half luck, half adjusting my artwork to the direction of the veining.
Here is my chip of this acrylic so you can see how it’s swirled. Super gorgeous material:
My weld skills are quite poor, I assure you. It had some gloobers so I sanded and buffed down the surface to a soft matte finish. I intended to polish it, but I actually like the matte texture so I left it. For me, what helps is using a weld cement with “body” to it. I used Sci-Grip medium body weld. Use sparingly, it does tend to get melty. But use enough to fill all the gaps. And don’t monkey with it til it’s dry. I had to learn that the hard way.