Anniversaries for dating
175 years is a quarter century less than the next whole (bi)century or 175 = (−25 200).
and this is perhaps a modern contraction of "de-quadrans".
Furthermore, there exist numerous partially overlapping, partially contradictory lists of anniversary gifts (such as wedding stones), separate from the 'traditional' names.
The concepts of a person's birthday stone and zodiac stone, by contrast, are fixed for life according to the day of the week, month, or astrological sign corresponding to the recipient's birthday.
Latin terms for anniversaries are mostly straightforward, particularly those relating to the first twenty years (1–20), or multiples of ten years (30, 40, 60, 70 etc.), or multiples of centuries or millennia (100, 200, 300, 1000, 2000, 3000, etc.) In these instances, the name of the anniversary is generally derived from the Latin word(s) for the respective number of years.
In any event, if such a conjunction was appropriate then it would perhaps more likely have been "Dosquibicentennial" (but the result is little shorter anyway). Chapman to William Safire; first appeared in Safire's column, "On Language" (The New York Times Magazine, February 12, 1995).An anniversary is the date on which an event that took place or an institution was founded in a previous year, and may also refer to the commemoration or celebration of that event.For example, the first event is the initial occurrence or, if planned, the inaugural of the event.In Latin this is "Sestertius" which is a contraction of semis (halfway) tertius (third)—hence Sestercentennial.A modern coined term; sesquarcentennial for 350 years is deduced here from the "Sestertius" definition for 250 years above.