I have looked through other threads with similar issues, but it seems like people have been just looking in the wrong place. This seems like something else.
I'm playing on the latest build in survival mode in a default settings world that we created a few weeks ago, and I have not found a single Lapis ore. I've strip mined huge sections in levels 6-10 and in levels 13-16 and found LOTS of diamonds, redstone, gold, iron and coal. I am exp level 45, and have created enchanting table with full bookshelves, and can't enchant because I cant find a single stinking Lapis. I just spent like 2 hours strip mining 13-16 and gone through dozens of pick axes. Nothing.
According to gamepedia it should occur at about .083% at those levels. I've got chests full of cobblestone from this strip mine, so like cobblestone in the thousands. I should have found dozens of Lapis if those numbers held up.
This has never happened to me before. Any ideas? Is it possible for the world to be bugged and just not have any?
Lapis is essentially as common as Diamond, so the Wiki is basically wrong or perhaps at some point the distribution was changed. I seem to recall (by feel, as I generally go caving instead) Lapis being a bit more common a few steps up from what the wiki says.
I know it's hard to resist and boring as sin (without resorting to cheaty commands), but you might want to just pick a few chunks and use commands to delete all the stone/dirt/gravel/etc and try to get in there to look at the ores. Maybe do this in separate sections so you can highlight each ore individually (ie, section one leave only the coal, section two leave only the iron, section three leave only the lapis, etc).
The Wiki is still mostly correct about how lapis generates, aside from how common it is, which uses a figure from 1.6.4 or earlier (all ores are around 20% more common in 1.8 and later, mostly due to an increase in the size of all veins by one). Unlike most ores, it generates with a triangular distribution which peaks at about 0.1% of all blocks on layer 15, with a range of 0-30 (not 31), with veins extending down from their starting point so there is slightly more just below this layer than above (and yes, 0.1% is correct; it only seems more common when branch-mining because you expose many blocks per block mined and you can intersect a multi-block vein with relatively sparse tunnels; according to data here diamond can be as much as 1.7% of blocks mined despite being only around 0.125% of all blocks between layers 5-12, making it effectively nearly 14 times more common).
Here is a relatively up-to-date chart of ore distribution (as of 1.12.2*); you can see that lapis peaks at around 0.1% of all blocks on layer 15, with slightly more below this layer than above; if you mine on layers 11-12, the usual diamond branch-mine level, you'll find about as much lapis as if you mined on layers 14-15 in 1.6.4 or earlier:
For comparison, this is a chart from 1.2.3, which would be the same as up to 1.6.4 (most of the Wiki's numbers on ore abundances have not been updated since then):
*It is probable that the amounts of ores changed in 1.13; snapshots had an issue with reduced amounts of ores so I presume they changed the generation algorithm and had to tweak it to get close to the original generation.
LoL, I launched the game this evening after checking on this post, went into the 13-16 mine, and literally the first block I uncovered was a lapis vein. Hows that for luck.... Or maybe Mojang was monitoring this and fixed my game, haha.