We were recently consulted regarding the annual Mahotsava and a Yantra Pratiṣṭhā at a temple of Bhagavatī Kālikā in Chennai. Several related Tantras were examined to find a suitable pramāṇa before ordering a specific Yantra. It seems to be a trend lately to prefer yantras made of gold. Several texts speak of the prāśastya of Svarṇa-yantra as next to only ratnādi-nirmita yantra (made of precious gemstones).
However, there is a certain clause in the Kālī Tantra that speaks of svarṇa yantra as being unsuitable in Kaliyuga. This instruction from the Tantra is generic and not specific to Kālī yantra:
svarṇādiracitam yantram satyādiyugasammatam |
jambudvīpasya varṣaṁ tu kalikālē ca bhāratē ||
svarṇādi racitē yantrē pūjanāt prakaṭaṁ bhavēt |
prakaṭē mantranāśaḥ syādvadhabandhanamēva ca |
prakaṭē siddhihāniḥ syāt prakaṭē maraṇam bhavēt ||
To understand this somewhat obscure verse, we had to refer to Pratiṣṭhā Chintāmaṇi of Vāsudēva Miśra and he seems to agree with this restriction when speaking of Durgā yantra sthāpana. He clarifies that Silver and Ratna are fine though, quoting from the Pāñcarātrāgama.
Again, what is true for arcā yantra is not the same for sthira or pratiṣṭhā yantras and the above prescription is only for a yantra worshiped by a upāsaka every day. That said, several luminaries intricately familiar with pratiṣṭhā procedures do not agree with this distinction between arcā and pratiṣthā as both are valid in this case and this particular Tantra does not seem to restrict its prescription to a particular kind. Moreover, the temple is administered by folks who follow Kālī Tantra as their mukhya pramāṇa, and it does make seem to make sense to abide by it and not use a svarṇa yantra.