total of 50:

Gold Ring - Multiple Places - Kill The Executioner at the end of chapter 1-1 for the earliest one.

Ivory Relief - Dropped by the blonde woman who's aid you come to in chapter 1-2

Dead Bride's Necklace - There are 2 lying near the discarded corpses on the conveyer belt in 5-2, or they are dropped by the Rocket Launcher wielding Majini in 6-1

Royal Necklace - Chapter 5-3, Inside the control room being guarded by a bunch of Rocket Launcher Wielding Manjini

Jewel Bangle - Kill a "Big Man Manjini"

Venom Fang - Kill a Chainsaw Manjini (The first one you encounter will not drop one unless you're on Veteran or above, in which case he will come back to life after dropping the key, and you can kill him again for the fang)

Antique Clock - Chapter 1-2. Out on the balcony of the house that is locked from the inside.

Chalice (Silver) - Multiple Places - One on the middle island of chapter 3-1, the chicken farm

Chalice (Gold) - Chapter 5-3 - In the room with the drawbridge and swarm of lickers, this is in a locker after you drop down into the locked room.

Silver Idol - On top of the left of the two assist jumps on the Northeast island in Chapter 3-1

Gold Idol - On the bottom floor of the mirror puzzles in 4-2, send the beam of light to the statue instead of the final mirror, this is in one of the rooms that unlocks.

Ceremonial Mask - In an alcove to the right of the gondola at the end of 3-1

Jewel Beetle - On top of the oil drums at the Tricell camp in chapter 3-2

Brown Beetle - Numerous in 3-1. There is one on the small island you start the chapter on.

Gold Beetle - On the bottom floor of the mirror puzzles in 4-2, send the beam of light to the statue instead of the final mirror, this is in one of the rooms that unlocks.

Topaz (Pear)- Numerous
Ruby (Pear) - Numerous
Sapphire (Pear) - Numerous
Emerald (Pear) - Numerous

Diamond (Pear) - After the scene with Irving in Chapter 2-2, go past the machine gun turret and aim at the top of the large ladder to shoot this down.

Topaz (Square) - Numerous
Ruby (Square) - Numerous
Sapphire (Square) - Numerous
Emerald (Square) - Numerous

Diamond (Square) - After the scene with Irving in Chapter 2-2 go past one more checkpoint. There is a broken ladder with an assist jump here, the Diamond is on the ledge Sheva lands on. Follow her around to where she climbs to and then jump down one level to get it.

Topaz (Oval) - Chapter 6-1 - Climb up all the ladders in the beginning of the Chapter and Shoot all Majini on the Crane so Sheva will not be caught later. The guy on the top left will drop the Topaz. Climb up the Ladder where you normally get caught and it's right in front of you. (Thanks SK L4xX)

Ruby (Oval) - Chapter 4-1 - Behind the red statue in the Labyrinth.

Sapphire (Oval) - Chapter 5-3 - During the Wesker/Jill fight after Wesker kicks you through the door turn around and follow the corridor into the room containing all the coffins/sarcophagi. The Sapphire is in a small pot on the shelf to the right as you enter.

Emerald (Oval) - Chapter 5-3 - During the Wesker/Jill fight after Wesker kicks you through the door turn around and follow the corridor into the room containing all the coffins/sarcophagi. The Emerald is in a coffin that needs an assist event to open.

Diamond (Oval) - Chapter 2-2 - In the mines just before the crank at the exit, turn left off the cart tracks and follow the wall to a chest containing the Diamond.

Topaz (Trilliant) - Chapter 4-1 - At the beginning before you climb up the first ladder go straight towards the end. It is in the treasure box found there. (Thanks SK L4xX)

Ruby (Trilliant) - Chapter 4-1 - After you fall down from the trap with the empty sarcophagus it's in one of the three treasure chests. (Thanks SK L4xX)

Sapphire (Trilliant) - Chapter 4-1 - After you fall down from the trap with the empty sarcophagus it's in one of the three treasure chests. (Thanks SK L4xX)

Emerald (Trilliant) - Chapter 4-1 - After you fall down from the trap with the empty sarcophagus it's in one of the three treasure chests. (Thanks SK L4xX)

Diamond (Trilliant) - Chapter 4-2 - After putting in all 3 Emblems in that door go up the stairs and shoot it down right above the big door you have to enter.

Topaz (Brilliant) - Chapter 5-3 - In the room with the drawbridge and the swarm of lickers this is high on the wall in front of you as you cross the drawbridge.

Ruby (Brilliant) - Chapter 5-3 - Leave the room with the giant rotating elevator, then look on the ceiling between the last two lights as you emerge from the tunnel in the next room.

Sapphire (Brilliant) - Chapter 5-3 - During the Wesker/Jill fight after Wesker kicks you through the door turn around and follow the corridor into the room containing all the coffins/sarcophagi. The Sapphire is in a coffin that needs an assist event to open.

Emerald (Brilliant) - At the start of the Wesker/Jill fight at the end of chapter 5-3 run up the staircase on the right in front of you and follow the path round to the right. The Emerald is in one of the pots at the end.

Diamond (Brilliant) - Chapter 2-2 - After the scene with Irving, do downstair and outside. Walk towards the machine gun turret and look for a small ladder on your left. The Diamond is in a chest on that ledge.

Topaz (Marquis) - Chapter 1-1 - After you jump out of the Window take out all the Majini you normally run away from. One of them will drop it. There are a lot of them, so be patient.

Ruby (Marquis) - Chapter 2-1 - During the fight in the market area where you have to shoot a key from a hanging dead body, toss a grenade into the middle stall with a chest in it, the Ruby is in that chest.

Sapphire (Marquis) - Chapter 5-3 - Right at the beginning of the level, leave the boss room, follow the path around and take a left at the fork, the Sapphire is in a safe to your left as you enter the room.

Emerald (Marquis) - Chapter 3-3 - After leaving the boat for a second time, climb a ladder to the ledge with the two machine gun turrets above the gate you're trying to open. The Emerald is in a drawer in the room between the guns.

Diamond (Marquis) - During the final fight with Wesker in the volcano, right after Wesker appears for the first time, turn around and head towards the bridge that will collapse. Before stepping on it though, shoot down the rock just past it that is the same colour. Now when you fall through the bridge, turn to your left and jump over the rock to retrieve the diamond.

Power Stone - Kill a Reaper

Lion heart - Kill a Licker (This is not a 100% drop, but at least one out of every group should drop one)

Blue Enigma - Kill a Giant Manjini (The tribal leaders in 3-1)

Soul gem - Kill the boss at the end of 4-1 without using the reaction event, i.e kill him before climbing the stairs to the exit.

Heart of Africa - In between the stairs during the Jill solo fight in 5-3 but only if you ended the previous fight by damaging Wesker enough to make him retreat.

I saw this guide on Xbox360Achievements.org earlier this week. I suggest you ask for permission to post this, otherwise it's plagiarism.

Edit: Found the guide I was talking about. I know it's the same one because of the "Numerous" for the common-type gems.

I always go to X360A.  Their achievement guides are the best on the net.  Also plagiarism FTL.

"first off that's not where I got it from, second I'm just bringing it to more people that might like to see it making giantbomb the one stop shop for everything and lastly you guys can fuck off your high horses, god is everyone on this site a complete asshole?"

"first off that's not where I got it from, second I'm just bringing it to more people that might like to see it making giantbomb the one stop shop for everything and lastly you guys can fuck off your high horses, god is everyone on this site a complete asshole?"

"alright I'm sorry that I dared to even think about posting something on here because I'm just a lowly peasent to you massive assholes
"

"Azteris said:

"prinny_god said:

"alright I'm sorry that I dared to even think about posting something on here because I'm just a lowly peasent to you massive assholes
"

Instead of trying to call everyone assholes for (correctly) calling you out on cribbing from other people's shit, why don't you just learn and let go?"

its a two way street you guys didn't have to be such jerks you could have said "oh that's where the stuff is" and moved on or maybe crazily you guys could have said nothing "

"prinny_god said:

"Azteris said:

"prinny_god said:

"alright I'm sorry that I dared to even think about posting something on here because I'm just a lowly peasent to you massive assholes
"

Instead of trying to call everyone assholes for (correctly) calling you out on cribbing from other people's shit, why don't you just learn and let go?"

its a two way street you guys didn't have to be such jerks you could have said "oh that's where the stuff is" and moved on or maybe crazily you guys could have said nothing "

So your saying we could have just not criticized where criticism is do? I don't think that qualifies it as a two way street. Just let it go, no one here is saying your a terrible human being or anything, we all make mistakes."