Mold Seam: Mold seam stop at should seam--- about 1800; Mold seam stops between shoulder and top of neck-- about 1875; Mold Seam stops nearly at top of the neck-- about 1890; Mold seam stops at top of neck---about 1900; Mold seam top of bottle about--- 1910 and later. Study and take a look at my antique medicine bottles. Please sign my guest book. Thank you and Best Wishes! vicky