This is a playful and clever sterling silver chocker style necklace which comes with matching screwback earrings. The demi parure is extremely well made in Taxco, Mexico, before 1948. The technique developed by Los Castillo is called "onix negro", a technique whereby the onyx is incised and the silver inlay is securely tapped into the incisions. They are snugly held in without any binder and appear to be as one. Makes a nice contrast, the silver against the black. One can read more about this technique in "Mexican Silver" a book by Dr. Penny Morrill and Carole Berk. This necklace is composed of squarish onyx pieces set into a silver frame with inlaid bubble blowing fish. Each inlay is separated by undulating silver bars that are designed in three sections. Necklace flows beautifully. The closure is a box and tongue type which keeps the integrity of the flow. It closes securely with a firm click. Earrings match the "onix negro" fish on the necklace. They have not been worn as much as the necklace so the onyx pieces have more sheen. This could be achieved with a special polishing by a professional if one preferred that look. The silver is uncleaned and has developed a warm rich patina. The necklace measure: 15.5" when open or 15.25" when closed. The links are 1/2" wide, the onyx pieces are 3/8" by just over 5/8". Earrings are the same size as onyx pieces. Though hallmark is worn one can make out Sterling, 925,Taxco, Mexico. Artist initials are no longer legible. A stamp can also be seen under the screwback of one earring. In excellent vintage condition with only minor surface wear from age and use. It would be a great addition to any silver collection or a Mexican silver collector!