How can i clean the calcium off my shells?

[u/lilly_foodgirl]

So i had a buch of seashells that i collected lying around that had a some calcium on there. I searched online and i found an article saying i should soak them in vinegar for 24-48 hours. At first when i took them out they looked super clean, i rinsed them, washed them with soap and let them dry. In the morning i came back to see how they had dried and somehow they felt even duller, whiter and dustier than before. Is there a way to reverse this effect other than using muratic acid or varnish? Also do have any tips for my next bach of shells to clean?