I recently acquired an assortment of pocket watch crystals, with the labels still attched. The listing said some of the crystals were for hunting cases. I'm trying to figure out which these are.

Some of the labels have a third number, a 5, 6, or 7. I read in another topic that the third number represents the crystal's profile. Compared to the others, these have a low profile and very thin glass. Would I be correct to say that these are the hunting case crystals?

Thanks,

Christopher,

If the crystals are very thin and have a single digit number such as 6,7 or 8 than they are hunting crystals. Although I should know the exact formula, I don't but that number represents the height of the glass and the numbers range from 1 which is the tallest to 8 which is nearly flat. I had better brush up on my history though as I plan on supplying these in the near future.

William

The single digit numbers do refer to height as William writes. According to my information, 6 & 7 are common HC heights with 8 being very near flat. The crystals need height to allow the hands to rotate yet be flat enough to allow the front lid of the case to close.