Rare ,Vintage MCM Birks Sterling Silver Mayonnaise Bowl With Cobalt Color Glass

This was my Grandmother Nelles, who was a wonderful cook and always set a beautiful table. This is modern looking Birks, Sterling bowl, with separate cobalt colored glass liner. I have not seen another like it. Ive seen smaller salt servers, but nothing this size It has a little tarnish, but no chips or dents. Its a lovely piece. It was used by my family as a centerpiece with flowers, and a nut bowl with cocktails, and for cold sauces/mayonnaise. It is marked Birks Sterling on bottom, With the 4 maker marks for Birks circa 1953 , and 46/53. I do not know what the 4th mark is or what it represents it looks like a woman's profile. It is 5" diameter X approx 2 3/4" High. The glass bowl fits snuggly inside silver bowl. Please ask for more photos.