Q = Will this crucible hold 25ml, as stated, with a lid on?
A = Yes, with 25ml of liquid in the crucible, the liquid level is still approx. 4mm below the crucible rim, so a lid can easily be fitted without any spillage.
Q = What grade of steel are these made from?
A = Stainless steel 304 spec 18/8 non-magnetic, bright finish. Nominal wall thickness 0.7mm.