Antique Silver Penannular Brooch, Massive & Heavy, Medieval Style

This is a rare and outstanding very heavy silver penannular brooch that was made, hand made, rather than cast and with a hexagon as each terminal, a fish on one and a portcullis to the other, both punch engraved, the body of the brooch is finished with a spiral design to the body, the pin is a simple spike with the barrel formed by wrapping it around the brooch and securing it with a double twist, punch engraved with a vague Celtic design to the barrel. Age: I do not know, it is a early design and there is very heavy wear to the bar a inch in from each hexagon which does imply heavy usage or usage over a long period. Xrf testing confirms silver but of a consistent standard, which possibly eliminates medieval, more than likely a Victorian copy. I have never seen anything like this before, the size, the weight, the way the spiral is cut, it is just so unusual. This type of brooch has been used so long by the human race, from the 3rd century B.C, and passed through so many different styles, that it cannot be said with certainty where it originated, nowadays it's mostly considered to be Scottish, 50 years ago, it was it was then considered to be Gaelic, if you think 800 years we would consider it to be Norse, if we look earlier than that we would think Roman and before that ancient.