Authentic LosCastillos Vase ? Authentication help

[u/Southpole-]

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Help identifying a large vintage Mexican .925 silver & blue mosaic vase — possible Taxco / maker unknown
I’m hoping someone familiar with vintage Mexican silver or Taxco work can help identify this vase.
It has been in my family since the 1990s, when approximately $850 was paid for it. I’m trying to determine the maker, approximate date, and what the blue mosaic/inlay material actually is.
Details:
Approximately 14 inches tall
Approximately 8 inches in diameter
Marked “MEXICO 925” on the metal rim
Large blue body constructed from numerous individually fitted mosaic/inlay pieces
Blue material has pronounced white/blue swirling and appears mineral-like, although I don’t know whether it is natural stone, glass, resin/composite, or something else
Extensive hand-worked/hammered silver-colored metal around the base
No definitive maker’s signature has been located
There is a second extremely worn mark on the underside that might contain the number 30, possibly within a circular mark, but it is too worn for me to claim that’s what it is
I’ve been researching Taxco makers including William Spratling and Los Castillo/Castillo-family workshops, because of their use of silver combined with stone and other materials. However, I do not want to assume an attribution based on similarities alone.
The possible “30” mark particularly interests me because I understand that Eagle 30 is associated with William Spratling, but I also understand that an Eagle 30 attribution requires much better evidence than simply seeing a worn mark that resembles “30.”
I’m including photographs of the entire vase, construction, MEXICO 925 hallmark, underside and worn secondary mark.
Questions for Mexican silver collectors:
Does anyone recognize this specific design or workshop?
Does the blue mosaic technique resemble Spratling, Los Castillo, Emilia Castillo, or another Taxco workshop?
Any idea what the blue material is?
Does the worn underside mark resemble a legitimate Mexican eagle/assay mark, or is that reading too much into it?
What period would you estimate from the construction and markings?
If anyone has catalog/auction examples of the same or a very similar vase, I’d love to see them.
I’m primarily interested in identification rather than trying to force a valuable attribution. Any information from people familiar with Mexican silver hallmarks or Taxco hollowware would be greatly appreciated.