Ghost PStones / Residual PS Fields

[Th3Element05]

I encountered a phenomenon recently in an area I was mining, Ph0 checked it out with me and I said I'd post about it in the bugs section.

In this area I had placed a diamond block, later I moved that same pstone to another location (this happened to be at the same x/z coords, but much lower below ground).  I did this by breaking the block, then going and placing it in its new position.
Later on, I was clicking blocks with my pick to check their protection, and it returned:
City Protected: x, 65, z
City Protected: x, 8, z
Listing both the current and previous location of the pstone.  Ph0 confirmed that there was no pstone in the previous location listed.
I did not experiment with the bug any further, yet.

I do recall recently watching from irc, bk was trying to help platy recover some pstones that /ps location was telling her existed, but that neither of them could locate them.  I believe they were encountering the same "ghost pstone" issue that I found.

[micahdg]

What are the actual locations of these fields? And which world?

[Th3Element05]

They were in the regular survival world.

I experimented with the fields more:
I went to the location listed, and placed a cobblestone block in the exact location that there was supposedly a pstone.  Then when the cobblestone block was clicked with a tool, it returned pstone info as if you clicked a real pstone.  When this cobblestone block was broken, it dropped a diamond block.  This was in the Overworld.
I was able to replicate this on another ghost pstone of mine that I found.  This one was in the End.

I am not 100% certain, but I am pretty sure, that when I originally broke the pstones which returned as ghosts, that the did in fact drop a diamond block when broken.  If they did drop resources when they were originally broken, then as a result of replacing the ghost stones with cobble, and breaking them for diamond blocks, I may have transmuted two cobblestone blocks into diamond blocks due to this glitch.  I will be paying more specific attention to whether or not my pstones drop when I break them in the future, so that if I come across any more ghost pstones, I can say with certainty whether or not diamond (and presumably emerald) blocks can be duplicated when this bug occurs.
I was unable to replicate the ghost pstone bug intentionally when I tried, but still, with the possibility of this bug leading to duplicated blocks with such a high value, it definitely needs to be looked into asap.

Ph0 said that he also experienced a diamond block dropping when he broke the block that was occupying the space where Platy had a ghost pstone.

[micahdg]

If you'll toss me some coordinates for these ghost PS fields I'd like to look in the database and see what's there.

[micahdg]

With the assistance of kealper I think we have solved this problem moving forward. If you still have a ghost field, I'll be happy to help delete them but they should not be created anymore upon server restart. If you find otherwise, please let me know asap.