Qualifying Child. To be considered a qualifying child, your grandchild must be under the age of 19 on the last day of the tax year, or if he's a full-time student, under the age of 24.No age restrictions apply, however, if your grandchild is permanently and totally disabled.ualifying Child. To be considered a qualifying child, your grandchild must be under the age of 19 on the last day of the tax year, or if he's a full-time student, under the age of 24.
Platinum-iridium alloy. Platinum-iridium alloys are alloys of the platinum group precious metals platinum and iridium. Typical alloy proportions are 90:10 or 70:30 (Pt:Ir). These have the chemical stability of platinum, but increased hardness. The Vickers hardness of pure platinum is 56 HV while platinum with 50% of iridium can reach over 500 HV.
Platinum belongs to the family of metals like ruthenium, rhodium, palladium, osmium, and iridium. Platinum dates back its origin to the Egyptian tombs in 1200 BC. The Egyptians during this time imported the metal platinum from Nubia.latinum belongs to the family of metals like ruthenium, rhodium, palladium, osmium, and iridium. Platinum dates back its origin to the Egyptian tombs in 1200 BC. The Egyptians during this time imported the metal platinum from Nubia.