The seer stone narrative has troubles. An important part of Joseph Smith's early life was a seer stone by which he claimed to be able to find hidden treasure.  (Here is some information from the official LDS Web site about his practices and the existence of the stone.)

Researcher Bruce MacArthur has posed some interesting questions about the seer stone. Anyone want to tackle answering?

The FIRST is this: According to Martin Harris, Joseph Smith used his
“seer stone” to locate the plates of gold.  On the other hand, the Pearl
of Great Price; Joseph Smith — History 1, verse 42 ends with these
words —

“.. While he {Moroni} was conversing with me about the plates, the
vision was opened to my mind that I could see the place where the plates
were deposited, and that so clearly and distinctly that I knew the place
again when I visited it.”

It seems to me (1) that either story “might” be true, or (2) that
neither story is true — but that both stories simply cannot be true!
IF my logic is correct, then “the Mormon story” is knowably false when
it asserts that both are true.  What Mormon perspective am I still
missing that might explain this apparent discrepancy?

The SECOND has to do with the famous first 116 pages of Book of Mormon
manuscript which were “lost” by Martin Harris — possibly, according to
some, burned by Martin's wife in her kitchen.  This loss occurred during
a period when everyone agrees that Joseph Smith was using the “seer
stone”.  It is true that he was, in this time-frame, using the “seer
stone” for “translation”, but he had a few years of experience using it
to find lost objects.

If either Joseph Smith or Martin Harris had been correct in trusting the
“seer stone” to let Joseph Smith see the location of lost objects, why
is it that he did not even attempt to use the “seer stone” for its
original purpose in this most desperate of circumstances?  Is not this
failure tantamount to an admission that the entire “seer stone” story
was known — BOTH by Martin Harris AND by Joseph Smith — to be entirely
fraudulent?  Do Mormon leaders have a likely answer for this question
that goes beyond reciting their respective “testimonies”?

For more information, see The Mormon Mirage 3rd Edition:  A Former Member Looks at the Mormon Church Today(Zondervan, 2009). Also available as an audiobook and as an expanded-text E-book for Nook, Kindle and other reading devices.