Thought some of you might find this interesting. All skill levels posted include 5% geerlok. My char has 280 wisdom:
At 218 skill I attempted 10 ceramic swords of war:
-5 failures
-5 successes
Between 225 and 243 I attempted an additional 10 ceramic swords of war:
-5 failues
-6 successes
At 240 I attempted one ceramic skull of decay:
-1 failure
At 243 I attempted two ceramic hammers:
-2 successes
At 243 I attempted 3 more ceramic skulls of decay:
-2 failures
-1 success
Okay, this is not ceramic but have to post out of frustration. At 243 attempted 3 trophies and FAILED on all three
Azariah
65 druid
Tunare
At 218 skill I attempted 10 ceramic swords of war:
-5 failures
-5 successes
Between 225 and 243 I attempted an additional 10 ceramic swords of war:
-5 failues
-6 successes
At 240 I attempted one ceramic skull of decay:
-1 failure
At 243 I attempted two ceramic hammers:
-2 successes
At 243 I attempted 3 more ceramic skulls of decay:
-2 failures
-1 success
Okay, this is not ceramic but have to post out of frustration. At 243 attempted 3 trophies and FAILED on all three

Azariah
65 druid
Tunare