working directly with mandates/ manufacturers for portland cements from ukraine, russia china, indonesia and india. we have chosen these partners to work with after extensive research as they provide the most competitive prices in the market commodity grey portland cement for construction opc 32.5 n --------- opc 42.5 n ---------opc 52.5 n british standards bs 12/96 origin ukraine,russia, asia & india or seller choice chemical composition loss in ignition % 1,8 insolube residue % 0,8 sulphur trioxide% 2,7 magnesia mgo % 1,7 chloride % 0,07 na2o equivalent % 0,42 hypothetical compound composition trialcium silicate c3s% 54,4 dicalcium silicate c2s % 18,2 tricalcium aluminate c3a % 6,8 tetracalcium aluminoferrite c4af % 11,6 normal consistency % 27,5 fitness index (cm2/gm) 3040 initial setting time (hours:mins.) 3:25 hard set time (hours:mins.) 4:52 physical and mechanical properties compressive strength iso/en 196 mortar bs 4550 mortar 3 days (n/mm˛) 26,5 34,2 7 days (n/mm˛) 37,3 42,5 28 days (n/mm˛) 52,8 54,6 w/c ratio 0,5 0,4 description requirement typical analysis chemical analysis sio2 20.22 al2o 4.84 % fe2o3 3.36 % cao 62.48 % mgo 5.0 max 3.17 % so3 3.5 max 2.81 % na2o +0.658 k2o 0.61 % loi 3.0 max 1.84 % ir 1.5 max 0.62 % cao / sio2 2.0* max 3.09 % c3s c2s 66.7*max 71.5 % c3a 7.15 % c4af 10.21 % ci 0.10 max 0.022 % physical tests blaine 3250 cm2/g expansion (le chat) 10.0 max 1 mm compressive strength 2- days 20.0 min 24 n/mm2 28 � days 42.6** min 49 n/mm2 setting time initial (vicat test) 60 min 180 min