Lub iav yog Ameslikas tau los ntawm solidification ntawm acidic pob zeb ejected los ntawm volcanoes. Kwv yees li 3700 BC, cov neeg Iyiv thaum ub tau ua iav ornaments thiab iav yooj yim. Thaum ntawd, lawv
Txhawm rau txheeb xyuas lub raj mis, ua ntej saib qhov hnyav. Lub raj mis ntawm tib lub specification yog hnyav dua. Qhov thib ob, txiav txim seb lub raj mis hauv qab yog cov pwm tsis siv neeg (lub pwm tsis siv neeg kuj zoo dua
Txij li thaum lub xyoo no, tus nqi ntawm iav tau yuav luag "tawm mus tag nrho", thiab ntau qhov kev lag luam uas xav tau loj rau iav tau hu nws "tsis muaj kev cia siab". Tsis ntev tas los no, qee lub tuam txhab vaj tse tau hais tias
[kev tsom xam kev lag luam] Raws li cov xov xwm, qhov poob ntawm lub periphery muaj qee yam tsis zoo rau kev sib koom, yog li kev lag luam qhib qis raws li tau teem tseg thiab sib sau ua ke tsis muaj zog; Nyob rau hauv cov nqe lus ntawm trading ntim, w
Lub tuam txhab no tuaj yeem ua tau raws li peb cov kev xav tau ntawm cov khoom kom muaj nuj nqis thiab lub sijhawm xa khoom, yog li peb ib txwm xaiv lawv thaum peb muaj kev yuav khoom.