Hecho Mexico Sterling Brooch HT

The markings are very clear on this heavy sterling Mexican brooch (21 grams). Measuring 1 3/4" by almost 1", the circular patterns are very 3-dimensional. There is no eagle mark on this piece or TF so it would date the piece to pre 1947. It is stamped Hecho en Mexico (Made in Mexico) and DF (District Federale), 925, a conjoined HT and Sterling. It is difficult to determine but in the center of each of the spirals, there appears to be either an area of the silver that was not polished flat or it is glue residue from perhaps an amethyst stone so we are selling the piece as found and have reduced the price substantially by offering a further reduction in our Spring Sale.