This mark refers to wholesale jewelers H Nathan and Co of Fore Street, London.
It's simply the manufacturer's name, short for "H and Company" - which would make it probably a UK rather than US firm.
A ring with the imprint H925 typically indicates that the ring is made of sterling silver, which is 92.5% pure silver. The "H" likely stands for "hallmark," indicating the authenticity and quality of the metal.
co² = co² + h²o = h²co₃ = hco₃ -1 = h+ = h+ = co₃ - 2
The nine to five states that the ring is at least 92 .5% sterling silver and the H is the Maker's Mark to ensure that the identity of the stamp is valid
William H. Block Co. was created in 1896.
William H. Block Co. ended in 1987.
H. C. Prange Co. ended in 1992.
H. C. Prange Co. was created in 1881.
Co (like in co-worker) hairor co (like in co-worker) h (hard h) eh(short e) r
Steven H Silver was born on April 19, 1967.
Steven H Silver was born on April 19, 1967.
h