Here is a vintage cut crystal and silver plated cocktail mixer marked “W” in a circle and underlined followed by an “A”. The “W” mark is that of Wilhelm Wolff of Pforzheim, Germany. Wilhelm Wolff began in business circa 1894 and I believe this mixer dates to the 1930s.
It measures approximately 9 3/8 inches tall and holds 3 cups. The silverplate does show wear. There are areas where it looks like there is a film and spotting on the plate. There is a very small section on the spout that is missing plate. I tried to take photos of this. I did see a couple of minor scuffs to the crystal but no chips or cracks. It is heavy in weight.
David Embury, in his 1948 book “The Fine Art of Mixing Drinks”, says that there are certain drinks such as the Martini and Manhattan that should have a ” scintillating translucence “. He states that shaking “muddies” or clouds the appearance of these drinks and both cocktails should always be stirred. He also says that metal conducts heat, therefore he recommends using a heavy glass mixer. Actually, it seems he is describing this mixer.
This mixer can be found here at my Etsy shop: https://www.etsy.com/listing/604557738/wilhelm-wolff-cocktail-mixer-cut-crystal