Which metal would strengthen my practice

One card came out: Three of Cups, reversed (single draw, position "current guidance").

That card doesn't name a metal — tarot has no metal for any card, including this one. The metal comes from the older suit–planet–metal correspondence, and Cups is water, ruled by the Moon, whose metal is silver. So silver is the traditional answer to your question, and the reversal is what decides whether it actually helps.

The reversed Three of Cups is celebration that has gone hollow: company substituted for the work, or the circle widened to cover something you'd rather not sit with alone. Read onto the silver question: silver works on this practice as a *reflective* surface — a mirror, a polished plate, a disc you look into — not as a token worn against other people. Polished metal in occult use has always been about seeing yourself accurately, not about protection or luck; the reversed card says the unpolished, decorative version is what you've already tried, or what would fool you.

The conditional: if your practice already involves objects, and what you want from a metal is a steadier mirror rather than a shield, silver is the one to sit with — and the test is whether you can use it without anyone else knowing it's there. If what you're actually short of is a practice you do *with* people, and the metal is meant to fix a loneliness the card is pointing at, then no metal on the table changes it; the reversed Cups says the weakening thing is the noise, not the missing talisman.

One step you can take alone tonight: set out the objects you already own for this practice and note which single one you reach for first when a reading goes badly. Whatever it is, that's the metal already in your practice whether you named it or not — and what you do next with it tells you more than any correspondence table.

One thing I'd need to sharpen this: when you say *practice*, do you mean the reading work itself, something ritual you do with objects, or something else entirely? The answer changes which reading of the reversed Cups is the live one.