And þerfore whan grete lordes and knyghtes gon to seche worschipe in armes, þei beren gladly the dyamaund vpon hem. I schal speke a litill more of the dyamandes, allþough {110} I tarye my matere for a tyme, to þat ende þat þei þat knowen hem not be not disceyued be gabberes þat gon be the contree, þat sellen hem. For whoso wil bye the dyamand, it is nedefull to him þat he knowe hem, because þat men counterfeten hem often of cristall þat is ȝalow; and of saphires of cytryne {115} colour, þat is ȝalow also; and of the saphire loupe; and of many oþer stones. But, I tell ȝou, theise contrefetes ben not so harde; and also the poyntes wil breken lightly; and men may esily pollissche hem. But summe werkmen, for malice, wil not pollische hem, to þat entent to maken men beleue þat þei may {120} not ben pollisscht. But men may assaye hem in this manere: First schere with hem, or write with hem, in saphires, in cristall, or in oþer precious stones. After þat men taken the ademand, þat is the schipmannes ston, þat draweth the nedle to him, and men leyn the dyamand vpon the ademand, and leyn the nedle {125} before the ademand; and ȝif the dyamand be gode and vertuous, the ademand draweth not the nedle to him, whils the dyamand is þere present. And this is the preef þat þei beȝonde the see maken. Natheles it befalleth often tyme þat the gode dyamand leseth his vertue, be synne and for incontynence of him þat {130} bereth it. And þanne is it nedfull to make it to recoueren his vertue aȝen, or ell it is of litill value. Chap. xxvi (xxx), f. 112 a.