Oak leaf themed Japanese nabeshiki (trivet)

This cast iron trivet is 5.5" widest diameter x .5" high. It has no maker's mark and weighs about 11 ounces I had expected this to arrive with my winged horse trivet but apparently the Japanese dealer did not combine shipping though they mentioned doing so. Hmmm... Their images are not great, but I thought I would go ahead and post it to balance the other trivet from the same source. This trivet is oddly constructed of layers of cast iron. I am not sure how they were joined together. It shows a lot of wear and pitting. I suspect that the dealer cleaned it up. Guessing the leaves depict those of the Japanese Emperor Oak. Not sure of the symbolism.

https://en.wikipedia.org/wiki/Quercus_dentata