▁of ▁four ▁construction ▁phases ▁that ▁span ▁over ▁four ▁centuries ▁( 1 0 0 0 ▁– ▁ 6 0 0 ▁B CE ). ▁B ene ath ▁the ▁m ounds ▁and ▁pla zas ▁were ▁found ▁a ▁vast ▁array ▁of ▁offer ings ▁and ▁other ▁buried ▁objects , ▁more ▁than ▁ 5 0 ▁separate ▁c aches ▁by ▁one ▁count , ▁including ▁buried ▁j ade , ▁pol ished ▁mirror s ▁made ▁of ▁iron - ores , ▁and ▁five ▁large ▁" M ass ive ▁Of fer ings " ▁of ▁ser pent ine ▁blocks . ▁It ▁is ▁estimated ▁that ▁Mass ive ▁Of fer ing ▁ 3 ▁contains ▁ 5 0 ▁tons ▁of ▁carefully ▁finished ▁ser pent ine ▁blocks , ▁covered ▁by ▁ 4 , 0 0 0 ▁tons ▁of ▁cl ay ▁fill . ▁ ▁Also ▁un ear th ed ▁in ▁Complex ▁A ▁were ▁three ▁rect angular ▁m osa ics ▁( also ▁known ▁as ▁" P av ements ") ▁each ▁roughly ▁ ▁and ▁each ▁consisting ▁of ▁up ▁to ▁ 4 8 5 ▁blocks ▁of ▁ser pent ine . ▁These ▁blocks ▁were ▁arranged ▁hor izont ally ▁to ▁form ▁what ▁has ▁been ▁various ly ▁interpreted ▁as ▁an ▁orn ate ▁Ol m ec ▁bar - and - four - dots ▁mot if , ▁the ▁Ol m ec ▁Dragon , ▁a ▁very ▁abstract ▁j agu ar ▁mask , ▁a ▁cosm ogram , ▁or ▁a ▁symbol ic ▁map ▁of ▁La ▁V enta ▁and ▁en vir ons . ▁Not ▁intended ▁for ▁display , ▁soon ▁after ▁completion ▁these ▁pav ements ▁were ▁covered ▁over ▁with ▁colored ▁cl ay ▁and