When an in-game item has an artificially inflated price that is almost completely unchangeable due to its long history of remaining artificially inflated. The act of creating a diamond lock on an items' price is often caused by one of two things:

1. A lull in the market, leaving it open to one person to name a price, and then others following in that price point out of lack of marketing information about the item. One of the ways this can be fixed is waiting for another pause in the availability of this item, and taking it upon yourself to name a more reasonable price.

2. In the earlier stages of the game the item was once rare, but is no longer rare (or AS rare as before). In this case the item trickles slowly into the market more frequently, people somehow do not realize the quantity has risen, and continue to use the old price. This causes a VERY permanent diamond lock effect that is incredibly difficult to stop, and is often only fixed by the webmaster/owner/team of overlords handing this item out in a very public way, making the quantity of this item more easily tracked.
Example 1:
Hotdogluvr27: Why is piece #1 of the Secret Lab Map so ridiculously expensive when there's so many of them?
ZapMasterDre: They weren't always plentiful, so they were more expensive. Now that there ARE more of them, they're supposed to cost less; but people are greedy and haven't been willing to adjust the price to the quantity.
Hotdogluvr27: Fucking diamond lock.

Example 2:
B4G3LD00M: All of these Royal PBs are like 1.75mil without fail...
DownPorridge: Just buy a new one from the Hidden Tower.
B4G3LD00M: How much more NP is it?
DownPorridge: None. It's the same price AND you get an Avatar.
B4G3LD00M: Why do people use the original price?!?!
DownPorridge: Idk diamond lock I guess
by Lukey.V October 17, 2014
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