Possibly better asked in Player Questions, or the Tankers forum? (This one's more for people to publish "How to" guides rather than questions on specific builds...anyway, I'll press the button to give GhostRaptor a wave, and let him decide. 
)
Also, some existing guides for Stone/Stones can be found here.
I'd say that having Hurl Boulder is like already having Provoke except with -fly and some damage 
I wouldn't bother with provoke.
I don't quite get conserve power on a stonetank. You resist end drain and Stonetanks become friends with every kin in town.
Energy Torrent and not Tremor? Are you sure? Lower aoe dps and spectacularness.
Id advise on crystal armour at anytime before 24. Haste before Granite.
1 acc is generally enough with a foc acc that has no to-hits in it in pve. I could be wrong though as I have foc acc with Invuln. I could easily be out 3 end slot foc acc anyway. Hurl can come late.
End slot attacks before toggles. In fact the way I'd have it is no end slots on toggles.
Damage slots in mudpots increase your level of threat too and I think they are better than taunt slotting atleast to help cut the numbers around you.
From being able to slot 25s start getting into IOs.
He will honor his words; he will definitely carry out his actions. What he promises he will fulfill. He does not care about his bodily self, putting his life and death aside to come forward for another's troubled besiegement. He does not boast about his ability, or shamelessly extol his own virtues. - Sima Qian.
Can anyone make me a build for my Stone/Stone tank? I made my own but I am not sure if it is any good here it is
Hero Plan by Mids' Hero Designer 1.30
http://www.honourableunited.org.uk/mhd.php
Level 50 Magic Tanker
Primary Power Set: Stone Armor
Secondary Power Set: Stone Melee
Power Pool: Teleportation
Power Pool: Fitness
Power Pool: Presence
Power Pool: Speed
Ancillary Pool: Energy Mastery
Hero Profile:
Level 1: Rock Armor <ul type="square">[*] (A) Defense Buff[*] (3) Defense Buff[*] (3) Defense Buff[*] (11) Endurance Reduction[/list]Level 1: Stone Fist <ul type="square">[*] (A) Accuracy[/list]Level 2: Stone Skin <ul type="square">[*] (A) Resist Damage[*] (13) Resist Damage[*] (19) Resist Damage[/list]Level 4: Earth's Embrace <ul type="square">[*] (A) Recharge Reduction[*] (5) Recharge Reduction[*] (5) Recharge Reduction[*] (7) Healing[*] (7) Healing[*] (13) Healing[/list]Level 6: Mud Pots <ul type="square">[*] (A) Endurance Reduction[*] (15) Endurance Reduction[*] (19) Taunt Duration[*] (40) Taunt Duration[/list]Level 8: Rooted <ul type="square">[*] (A) Healing[*] (9) Healing[*] (9) Healing[*] (15) Endurance Reduction[/list]Level 10: Taunt <ul type="square">[*] (A) Recharge Reduction[*] (11) Taunt Duration[*] (31) Recharge Reduction[*] (31) Taunt Duration[/list]Level 12: Recall Friend <ul type="square">[*] (A) Interrupt Reduction[/list]Level 14: Teleport <ul type="square">[*] (A) Endurance Reduction[/list]Level 16: Swift <ul type="square">[*] (A) Run Speed[*] (17) Run Speed[*] (17) Run Speed[/list]Level 18: Health <ul type="square">[*] (A) Healing[*] (45) Healing[*] (46) Healing[/list]Level 20: Stamina <ul type="square">[*] (A) Endurance Modification[*] (21) Endurance Modification[*] (21) Endurance Modification[/list]Level 22: Heavy Mallet <ul type="square">[*] (A) Accuracy[*] (23) Accuracy[*] (23) Damage Increase[*] (27) Damage Increase[*] (27) Damage Increase[*] (29) Recharge Reduction[/list]Level 24: Build Up <ul type="square">[*] (A) Recharge Reduction[*] (25) Recharge Reduction[*] (25) Recharge Reduction[/list]Level 26: Minerals <ul type="square">[*] (A) Defense Buff[*] (34) Defense Buff[*] (37) Defense Buff[*] (37) Endurance Reduction[/list]Level 28: Hurl Boulder <ul type="square">[*] (A) Accuracy[*] (29) Accuracy[*] (36) Damage Increase[*] (36) Damage Increase[*] (36) Damage Increase[*] (37) Recharge Reduction[/list]Level 30: Provoke <ul type="square">[*] (A) Accuracy[*] (31) Accuracy[/list]Level 32: Granite Armor <ul type="square">[*] (A) Resist Damage[*] (33) Resist Damage[*] (33) Defense Buff[*] (33) Defense Buff[*] (34) Resist Damage[*] (34) Defense Buff[/list]Level 35: Stone Mallet <ul type="square">[*] (A) Accuracy[*] (43) Accuracy[*] (46) Damage Increase[*] (46) Damage Increase[/list]Level 38: Seismic Smash <ul type="square">[*] (A) Accuracy[*] (39) Accuracy[*] (39) Damage Increase[*] (39) Damage Increase[*] (40) Damage Increase[*] (40) Recharge Reduction[/list]Level 41: Focused Accuracy <ul type="square">[*] (A) Endurance Reduction[*] (42) Endurance Reduction[*] (42) Endurance Reduction[*] (42) To Hit Buff[*] (43) To Hit Buff[*] (43) To Hit Buff[/list]Level 44: Conserve Power <ul type="square">[*] (A) Recharge Reduction[*] (45) Recharge Reduction[*] (45) Recharge Reduction[/list]Level 47: Energy Torrent <ul type="square">[*] (A) Accuracy[*] (48) Accuracy[*] (48) Damage Increase[*] (48) Damage Increase[*] (50) Damage Increase[/list]Level 49: Hasten <ul type="square">[*] (A) Recharge Reduction[*] (50) Recharge Reduction[*] (50) Recharge Reduction[/list]------------
Level 1: Brawl <ul type="square">[*] (A) Empty[/list]Level 1: Sprint <ul type="square">[*] (A) Empty[/list]Level 2: Rest <ul type="square">[*] (A) Empty[/list]Level 1: Gauntlet
<font class="small">Code:[/color]<hr /><pre>| Copy & Paste this data chunk into Mids' Hero Designer to view the build |
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