Either Echeveria purple pearl or perl von nurnberg

Also very etiolated (stretched out) so it could use more light

Thanks Emily, that seems to fit pretty well I didn’t think echeveria could have stems like that! I’ve been struggling with with good lighting in my accommodation, will try another windowsill with better aspect.

Jaden

It should not have stem that long. Very top seems to be ok, but it definitely grew in light that was too low. Leaves should be bigger close together, and stem short and thicker. Consider getting a grow light if you don't have well lit windowsill. If you have access to any outdoors space your plant will like it :) Sudden increase in sunlight may cause sunburn, so make sure it is acclimatized to it.

To make it compact again, you would have to behead it. Read thru THESE THREADS to get lots of help and photos on how to do it. But you have to make sure it will be in better light, otherwise it will continue stretching/etiolate, and be overall weaker than it should be. It could be Echeveria Perle von Nurnberg.

If you don't mind me adding, I think I see sand mixed in that pot. While your plants may be growing much better out of terrarium (those are NOT suitable for succulents - even if they may look good to begin with...), sand could cause problems eventually. It is ok to add some if course, but fine sand most often comacts and interferes with good drainage. It is much better to add lots of sifted or rinsed perlite (or pumice) to your soil, mixing them thoroughly in 1:1 ratio. And any pot should have drainage hole(s).

Thanks Rina, that's all really really helpful! I really am considering investing in a grow light because I just can't seem to get great light in my ever-changing uni accomodations. I'll do a load of research and have a go at beheading and propagating as that seems to be the best for it. So the sand in the pot is horticultural grit sand I bought at the garden centre as they didn't have perlite at the time, it seemed as though it was aimed at cacti and succulents and I mixed it with a cacti/succuent/bonsai compost 70/30. Do you think I'm best off going back and trying to get some perlite and repot?

If it is coarse sand, it will work. I would check it for size by sifting it, using a kitchen sieve and use coarse parts that do not fall thru. So if coarse - keep it. t is difficult to judge size of it from the photo.

Many ppl do not like perlite because t is so light, and they find that it 'floats'. I use it a lot - pumice would be great but it isn't easy to get for me. I do not really have problem with perlite, because I use grit top-dressing (that keeps perlite in the pot).

I really like very gritty mix and use it for all succulents. It is approx. equal amounts of sifted or rinsed perlite and grit (I use chicken grit size #2). To that, I add small amount of turface, usually about 10-20%. Turface holds some water, but is also grainy. Sometimes, I substitute turface with soil or cocopeat, and it seems to work. No more than 20% of total (same as if using turface). I find gritty mix very well draining. Here is photo of it:

Many ppl use mix of C&S soil and perlite (or pumice) in 1:1 ratio, and seem to like it. It could be better to use in hotter and drier regions than I am in. It would retain some water bit longer. I keep plants outside spring to fall, and do not worry about them getting rained on - because mix drains fast. If no rain for a while, I just water with garden hose. So there are few options for good mix.

Since my plants have to be indoors for winter, I use lots of supplemental lights. You can buy 'fancy' grow lights...I use some CFL light bulbs, some LED light bulbs and also have LED tubes (if I have to get a new or additional, I get LED: they are more efficient). Make sure you get good light source; high k and lumens is what you are looking for...

Threads I linked to show beheading many different succulent. There are tips and photos from many members, so I think it helps.