I am a newbie to copper, but made a big leap (at least in $$) by purchasing several pieces. The two most significant and most expensive (!) are a 6 Gallon 12"x12" 2.5mm thick (minimum, it may be thicker but I don't have a caliper in mm, just inches) stock pot (yes, almost too heavy to lift even when empty) with the mark "Guillard Paris" and a casserole, with the same marking and thickness, that measures 10"h x 12"w. I also purchased several misc pieces, a copper bowl, a collander, a caramel pan, a very small sauce pan, etc.,. The lot was purchased for $350 at an estate sale. My questions are as follows:
1. Does anyone know anything about Guillard. I have not seen this line mentioned in any threads
2. Although no copper is showing through the tin lining, there are blackish areas on the bottom of the pans. I have cleaned them well and am now wondering if the black areas are a problem that will require me to re-tin the pots even though there is no visible copper.
3. If I wanted to resell the overly heavy stock pot, what would be a fair price (assuming it does not need re-tinning)?