Peridot belongs to the forsterite-fayalite mineral series which is part of the olivine group. It is one of the idiochromatic gems, meaning its color comes from the basic chemical composition of the mineral itself, not from minor impurities, and therefore will only be found in shades of green. In fact peridot is one of the few semi-precious gemstones found in only one color.
They have highly sensitive blood tests that can detect the pregnancy hormone (hCG) a few days earlier around day 3 to 4 after implantation. Again, some women have had positive urine tests as early as 2 to 3 days after implantation and others have had to wait up to a few weeks.
Implantation takes place when a fertilized egg is embedded into the inner wall of the uterus. This occurs about one week after your ovulation, although this may range from 6 to 12 days. It will take another 3 to 4 days (approximately 9 to 16 days post-ovulation) for your blood test to become positive. After 2 to 3 days an early urine test for pregnancy or a Home Pregnancy Test (HPT) may turn positive. In many women this test will be positive after they miss a period, which is approximately one week after the implantation of the fertilized egg. Although some manufacturers of home pregnancy tests say that the test gives positive results before you miss a period, only about a quarter of expectant women test positive two days before they miss a period, and less than half on the day before expected period.