Lavanya's grandmother has an old copper lota that has turned dull and brownish-black
Lavanya's grandmother has an old copper lota that has turned dull and brownish-black. Lavanya says copper is still a lustrous material — the shine is just hidden under a dull layer. Hamid says lustrous means shiny, and this lota is clearly not shiny, so this copper is not lustrous. Whose reasoning holds up?
Who do you think is right? Pick one.
The answer: Lavanya is right, a freshly cleaned surface of the copper will shine
Why
Hamid is going by what he sees right now, which is a fair place to start — the lota really is dull. But lustre is a property of the material itself, and you check it on a fresh surface, not an old one. Over months, the copper on the outside reacts slowly with air and moisture and forms a thin, dull coating; the copper underneath hasn't changed. That is why grandmothers scrub copper and brass vessels with tamarind or lemon: the sour juice removes the coating and the reddish shine comes right back. Test: rub one small patch of the lota with lemon and a pinch of salt, or rub it gently with sandpaper — that patch gleams while the rest stays dull. Same lota, same copper; only the surface layer changed. Lavanya is right: copper is lustrous, and a freshly cleaned or freshly cut surface shows it.
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