MRC:
Those unusual or unique characteristics or qualities of an item not covered in the other requirements and which are determined to be essential for identification.FEAT
Special Features:
Elements-concentration, ppm; ag: 900 plus or minus 1, fe: 900 plus or minus 1, pb: 900 plus or minus 3, ai: plus or minus 1, mg: plus or minus 2, si: plus or minus 1, cr: 900 plus or minus 2, na: 900 plus or minus 1, sn: 900 plus or minus 2, cu: 900 plus or minus 2, ni: 900 plus or minus 2, ti: 900 plus or minus 1
