What radioactive sources do you use and what do you store them in?

I have many. Maybe too many. 

Amerecium-241 - from smoke alarms. I have maybe 10.
Autunite U-238 - crystal/mineral
Caesium-137 - old spark gap
Depleted Uranium U-238/U-235 - check source from a Victoreen CD V-700 Model 6a (or maybe b)
Madagascan Blue Apatite NORM - Mineral
Potassium Chloride K40 - Granules
Radioactive Dirt-Dust U-238/U-235 - Is just dust/dirt
Radium Ra-226 in solution - nasty liquid in a jar.
6kg Uranium ore - some large rocks 
Radium painted watch hands R-226
Strontium-90 - old Soviet check source
Thoriated Cotton Th-232 - some strange old dirty, fluffy stuff with dirt and rocks in with it. No idea how it came to be.
Thoriated Gas Mantle Th-232
Thoriated Tungsten Rod Th-232 - welding rod
Thorium dioxide in solution Th-232 - small amount in a sealed vial with some unknown liquid
Trinitite - unknown what isotopes as is very weak - need to test on my Radiacode 103
Tritium - a small glow in the dark vial 
Uraninite (Pitchblende) U-238 - rock/mineral. I have a couple of these, one has some Gummite on it.
Uranium glazed pottery U-238 - a couple of pieces of broken pottery. One orange Fiestaware and another yellow, but unknown manufacturer.
Uranium glass - U-238 - green glass (the one in my avatar) and a couple of vaseline glass balls
Uranyl zinc acetate - in a small vial
Uranium trioxide - in a small vial
Yellowcake - in a small vial

You can see most of them here:  https://radmon.org/index.php/my-blog/simomax-s-sources-samples-updated-09-03-2023

Then there are all of the Thorium pendants, stickers and other Ju-Ju nonsense. Way too many to count. See here , here , here and here .

I think that is about it. The Amerecium-241 I get from old smoke alarms at work. The Thorium pendants, stickers and other Ju-Ju stuff, I got from AliExpress. Pretty much everything else came from ebay itself, or ebay sellers outside of ebay. Everything was posted to me, in regular shipping bags and envelopes. The radioactive dirt came from Germany and was just in a single plastic bag, inside a paper envelope. Yeah, proper dodgy. Nothing had been shielded, but then they are all low level, and on their own wouldn't trigger the postal radiation alarms. I looked into this not long ago and the postal services do screen post for radiation, but the machines they use are mainly on convayor belts where the post passes in front of them. They are generally set too high for these levels of samples to trigger them. The postal workers will initiate a manual check if either the conveyor belt detectors trigger, or by a call coming in - as in someone else alerted them to a possible radioactive something. My understanding is they generally don't care for the small samples and sources.

I started collecting back in 2016 when I got bitten by the Geiger counter bug. My wife and I have been collecting crystals and minerals for 30+ years and we have quite a large collection and some real showpieces. It seemed natural to try and collect as many radioactive minerals and elements and things when I got into Geiger counters and radiation, so I did. Getting all the Thorium Ju-Ju stuff was out of pure curiosity, and now I have over a hundred Th-232 check sources! (Maybe. It might not be quite that many, but certainly more than 50!)

How do I store them? Very bloody carefully!   Generally everything is separated and double bagged in small plastic sealable bags and then inside either a hard plastic or glass lab sample jar/bottle with screw lid. I have lots of varying sizes. Some, such as the 'Thorium dioxide in unknown solution' are inside a sample bottle with foam top and bottom and foam rings to hold it in the center. The Radium liquid is in (as it came in) a glass jar with metal lid (Polish baby food, I think). It's not ideal, but then neither is decanting it into something else. That is double bagged and then inside another thick walled glass jar with screw lid (a small Kilner jar maybe?) The Am-241 pellets are double bagged and in a little tin. Essentially, everything has a couple of layers of protection and then a hard shell. Some things don't need that level, such as the uranium glass, is just in a single plastic sealable bag. Then, some of the more sensitive and smaller specimens are inside a little lead-lined box ( see here ), then, they all go inside a thick wooden army surplus 'general use' box that is currently lined with old 3.5" hard drives (to be lead one day.) And that currently lives in the corner of my office, at home.

I can hear the cries already lol - 'What? Just in your office, there?', 'But...but...the radiation?' It's cool though, I have no worries about exposure from it. All of the specimens are quite low level. I think the Sr-90 is the hottest. I have three Geiger counters constantly running in my office. A Gk-Radmon with SBM-20  - this one is right beside me, on my left. A NetIO GC-10next with RD003 - this one is to the right of me. And an ESPGeiger HW with SBM-20 between me and the box of specimens, actually closer to the box than I - about 1.2m away. I am fully aware of the dangers, I take it seriously, and I take precautions. Probably more precautions than most people would. And, yes, I am nuts. I established that a long time ago.