כַּפְתֹּרֵיהֶ֥ם וּקְנֹתָ֖ם מִמֶּ֣נָּה יִהְי֑וּ כֻּלָּ֛הּ מִקְשָׁ֥ה אַחַ֖ת זָהָ֥ב טָהֽוֹר׃
זײערע קנעףּ און זײערע רערן זאָלן זײַן פֿון איר גופֿא, אין גאַנצן אײן אױסהאַמערונג פֿון רײנעם גאָלד.
Mishneh Torah, The Chosen Temple
When is the above law [that all the decorations are essential] true? When it is made of gold. However, [if it were made of] other metals, we do not make the cups, knobs, and flowers. Similarly, a golden Menorah must be one talent of gold, including the candles, and hammered out solid while [in the case of Menorahs made of] other metals we do not care about the weight, and it is Kosher even if it is hollow.