A1 is an English term for silver plate. Items with A1 are not sterling silver.
For =A1+B1, the operator is the plus sign (+).
A1 is a British electroplating hallmark and means superior quality. As this hallmark is for silver pieces and there is no mark allowed for gold plaiting it is most likely that you have a high quality silver plated piece that was further plated with gold. This is allowed under British law.
H100
A1 is an English term for silver plate. Items with A1 are not sterling silver.
Barker Brothers, Birmingham, England
A+ and A1+ refer to two different blood group systems. A+ is a type under the ABO blood group system, where A1+ specifically refers to subtypes within the ABO system that have additional antigens present. A1+ is a more specific classification within the ABO system than A+.
The Hallmark, Gilbert Marks....london 1861- 1905
what hallmark 923 mean on a bracelet.
What does the hallmark c963 mean
The mean of the numbers a1, a2, ..., an is equal to (a1 + a2 + ..., + an)/n. This number is used mostly as the average. It is called the arithmetic mean.
Not quite sure what your asking but hallmark is a company that makes different cards (I'm sure you know) but a hallmark can also mean