Quartz trades are typically always 1 emerald each.

Since upgrading the world to 1.15 (from 1.14) new villagers will lower cost of trades when a player has Hero of the Village effect EXCEPT for quartz blocks which go up (typically it stays at 1). This only happens to villagers who have their trades set during 1.15

Images below are of the same villager (had to scroll down 1). Notice the Hero of the Village effect on the top right. Furthermore notice that while one cost is cheaper, quartz has gone up.