Gambling for Charms and Amulets - Diablo 2
Using the Horadric Cube to Gamble for charms and amulets is one of the more common combines/gambling people do at a high level. Any 3 Perfect Gems + a Magic Item is all the combine takes, it'll reroll the Magic Item into something completely new which is usually total garbage.
While you can do this recipe on any item in the game it is most commonly used on amulets and charms, moreso charms. There are certain charms in the game called Baal Charms which are the highest ilvl charms in the entire game and are the charms which are typically chosen for this recipe.
3 Perfect Gems (Any Type) + 1 Magic Item = New Magic Item of Same Type
When you hear about gambling in Diablo 2 with Magic Items most people are probably talking about this recipe. To explain what this recipe does in a better way, it basically just rerolls the stats on an item. People like to do this with Charms to see if they can get anything good as well as with Amulets to see if they can get one for +2 to Skills. If you'd like to see what makes a good Amulet in Diablo 2 check out my what Amulets are worth keeping Guide.
This category is for the best Charms that you can possibly find in the game. Any Grand Charms you find that come with +1 to Skills and nothing else belong in the mediocre section below. Small and Medium Charms you're looking for max rolls along with a good combination of rolls. Max roll of a single Resist along with a max Life roll is an example of a good Small Charm.
Grand Charms: When you Gamble Grand Charms what you are looking for is + to Skills along with an additional roll like Life or Mana. Obviously the more popular class/spec charms will sell for more. Paladin Charms are typically the most popular with Sorceress being second. Any other Grand Charms with very high FHR, Max Damage, Attack Rating + a high Dexterity or Strength roll can sometimes be in this category too.
Small Charms: All Resist, Max (11%) to a single Resist, Faster Hit Recovery (FHR) as well as Faster Run and Walk (FRW) are imo the best stats you can get on a Small Charm. Certain builds don't get enough of these stats on their gear and need to supplement with Charms.
Large Charms: Max Magic Find or a max Life, Mana, Resist or All Resist roll. A Large Charm with at least two max rolls from these categories will be good. For the most part people typically do not use too many Large Charms; they don't have significantly better rolls than small, take up double the inventory space and can't get +Skills.
Poison and Bone is the most in demand Necromancer Grand Charm.
+32 Life is a mediocre secondary roll.
While not as valuable as Poison and Bone Skills, Summoning Skills still has value.
A very good roll for a Javezon Grand Charm. One point away from max Life.
Fire Skills is one of the less valuable Grand Charms since not many Sorceress are Fire in Hell.
7% Faster Run/Walk is the max you can get on a Grand Charm.
This is the highest Faster Hit Recovery (FHR) that you can get on a small Charm.
Paired with the highest roll you can get on a single Resist.
Max Life roll as well as a max All Resist roll. Definitely a valuable charm.
Life and Lightning Resist are both perfect rolls.
The Lightning Resist is good but 20 Life isn't all that hard to come by at levels 80+
Perfect Life roll and Cold Resist Roll. Same deal as above Charm.
Perfect Faster Hit Recovery (FHR) and Mana roll on a small Charm.
An extremely good combo; Sorceress' have slow FHR and Lightning is a popular spec.
This is a max Gold Find roll on the Grand Charm.
A mediocre Attack Rating roll with a perfect Life roll.
3 points from perfect Attack Rating roll and3 points from perfect Life roll.
It's up to you if you'd like to keep these sorts of Charms or keep gambling. All of the charms in this section are definitely still worth using but they aren't the best of the best that you can get.
Grand Charms: All Grand Charms with +1 to Skills but no secondary roll end up in this section. Also any Grand Charms that have +Skills and a secondary roll but the skill tree that they give +Skills to isn't very useful will end up here too.
Small Charms: Max All Resist roll is 5; Max Faster Run/Walk (FRW) roll is 3; Max Lightning/Poison/Fire/Ice resist roll is 11%; Max mana roll is 17; Max Life roll is 20; Max Poison DoT roll is 100
Large Charms: High Magic find rolls with high stat/resist rolls. For the most part people typically do not use too many Large Charms; they don't have significantly better rolls than small, take up double the inventory space and can't get +Skills.
This is the highest All Resist roll you can get on a small Charm.
Paired with a mediocre Adds Fire Damage roll.
This is the most FRW (Faster Run Walk) that you can get on a Charm.
Paired with a high amount of Poison DoT
Perfect Life roll; 1% from a perfect Lightning Resist roll.
Max Faster Run/Walk (FRW) roll with a max Mana roll.
Shadow Disciplines is not a very good skill tree to get a Charm for.
Faster Hit Recovery is a good secondary roll though and it is max.
Since this doesn't have a second roll on it, it's only mediocre.
These Charms are definitely still worth using but they typically have no trade value as they're common enough that people can obtain them on their own.
Grand Charms: Any Grand Charm you find with a combination or Life, Mana, All Resist, Lightning/Poison/Fire/Ice Resist, Faster Hit Recovery (FHR) and good rolls. Attack Rating, Max Damage and Dexerity or Strength is a good combo as well. Very few Grand Charms fall into this category. They're typically either trash or they have +Skills.
Small Charms: High rolls but not max of Life, Mana, All Resist, Lightning/Poison/Fire/Ice Resist, Faster Hit Recovery (FHR).
Large Charms: Mediocre Magic find rolls with high stat/resist rolls. For the most part people typically do not use too many Large Charms; they don't have significantly better rolls than small, take up double the inventory space and can't get +Skills.
Max Poison DoT and max Life roll.
Not many people want Poison DoT on their charm which is why it is mediocre.
Max All Resist with 6% Gold Find.
5 All Resist the max roll you can get on a small Charm.
Since this Charm only has one roll, it's mediocre
Highest Faster Hit Recovery (FHR) that you can get on a large Charm and decent Mana.
This is downranked to mediocre because it takes up 3 inventory slots and the mana roll isn't high enough.
Decent Life and Lightning Resist roll on a small Charm; neither are max rolls.
Decent Attack Rating and Life small Charm; neither are max rolls.