Gem collecting

Gems are collectibles in The Sims 3. They are found in their raw form and can be cut by sending them to a gem cutters.

Raw
Gemstones are found in the rough, around neighborhoods and on adventures.

Tiberium
Tiberium is an extraordinarily rare and potentially very valuable gem. The raw rock is worth §75-125. In the inventory (either as ore or cut) it will give a negative "Visceroidal Nausea" moodlet (-25 mood).


 * Getting tiberium
 * Break space rocks with the board breaker, requires level 9 Martial Arts (level 7 with Disciplined trait). Completing the Athletic Strength challenge is immensely helpful as the sim won't get fatigued
 * Exploring the mausoleum in the cemetery.
 * Sometimes relic vendors have them.
 * Transfiguration (only spire cut) - Combine an assortment of items (i.e., not all gems or bars) with a combined value of 3500-5000, and get a small spire back.
 * Using the miner can result in finding tiberium as well as other valuables
 * Rummaging for scrap in garbage cans can sometimes give uncut tiberium.

Tiberium in all forms has a green glow and will make a soft "ping" sound if placed on a lot.

This tutorial by GalaxyCommand shows how to make a spire cut pink diamond.

For §6500, get the gem spire-cut, which will in one day grow into a Large Spire (either in inventory or on the ground) which will sell for over §40,000 each.
 * Cuts

Alternatively, get the heart-shaped cut, which transforms into a Large Spire after a day, cutting §5,500 off the cost, or simply leave it in its raw form and it will grow into a spire cut thus saving the cost of the cut. However, this will take a few weeks.

Selling a heart-shaped cut or a small spire cut will roughly break even with the cost of cutting. Leaving tiberium in a sim's inventory for sometime will cause that sim to become sick (-25 moodlet).

Tiberium can "spread" as in multiply itself (which it does in the Command &amp; Conquer series). This duplicated tiberium behaves like an uncollected gem, so the player has to pick it up and put it back down before it can grow. The time it takes to do this is completely unconfirmed, though it appears to be somewhere in the region of 7-21 days.
 * Spreading


 * Trivia
 * Tiberium is a fictional substance that is central to the plot of much of the Command &amp; Conquer series, which is also made by EA. It could be used as both a power source and as a weapon. In the C&C series, Tiberium spreads very rapidly by changing the atomic make-up of matter, and the mineral is extremely deadly.

Cuts
Gems may be sent to the gem-cutter and cut into the following cuts. Starting with the emerald cut, and Sims gain cuts by cutting gems.

Geode & Septarian Nodules only have polished split and heart-shaped cut, while Tiberiums only have Spire and Heart-Shaped cut

Sometimes the gem cutters will return an uncut gem, saying that it is actually a Mysterious Mr. Gnome in disguise.

The table lists both when you break even with a particular cut, and when a cut begins yielding better profit than the previous cut.

For example, if a gem is worth §47, an oval cut provides §70 while the Pear cut yields §82. Factoring in the cost of the gem and the cost of cutting the gem, the Oval cut provides a §3 profit while the Pear cut yields no profit. The Pear cut does not start providing more profit than the Oval cut until the original worth is §60, as listed below.

Without mods, star-cut gems cannot be produced by players, but they can be found in tombs.