I am writing a book based around Wicca. I know a fair amount on the subject having been interested in it for many years, but I'm not so strong on knowing my crystals.
Due to the three fold rule, you don't find many negative uses for crystals, and this is something that I need to know, since there are some not nice people in my book.
Does anyone know a stone that would make someone compliant and not ask questions, or perhaps alter one's memories?
I think all crystals are used for good intentions.
The only negative outcome will appear when the crystal isn't cleaned, has bad energy input, or not suitable for you.
It's neat that you're writing a book. I hope it turns out well for you. :)
You often see in movies or TV shows, people using magick to alter individual things: memories, objects, themselves, ect. But they are just computer animated and created. For the visual appeal and entertainment only. You might be able to help someone forget about a memory, but it's still going to be there.
I've worked with stones for a long period of time, and some times they can be used for an alternative reason. Say, I have a Quartz that I store negative energy in when I get angry, sad, or I'm hurting, blah blah. You can store the negativity into stones, and then cleanse it once you feel it's needed. You can also use a stone to aid in "getting back" at someone, but it's just an aid.
Getting back on your original question, stones can't really control anything on their own. They can aid you, or give you a boost, but cannot do it on their own.
As far as properties and correspondences go, something that rarely gets discussed in occult literature of any kind, is that many natural substances contain both virtues and vices. (Ref Philosophy of Natural Magic, Henry Cornelius Agrippa for a wealth of information on the mechanics behind this phenomenon)
Basically, most crystals, herbs and other substances used in magick contain both positive, and negative properties, often in direct contrast to one another.
So an item that inspires courage also has the potential to inspire cowardice, love/hate, purity/toxicity, summon/banish etc. With the major distinction being the will of the user, and how the items are put to use, or in some cases how they are prepared for use. (Moon phase, planetary hours and alignments, use of specific symbols, colors or sigils to charge the items with various intent)
This is likely why many sources don't actually construct tables of correspondences for negative or undesireable effects. In most cases, take the virtues of the items your listing, and consider their opposites, and you've found (to some extent) the vices that correspond with that same item. Hope that helps.
Crystals are a direct link to the Earth. They are part of it as a baby is part of it's mother. They vibrate and resonate in natural currents, often influenced by their surroundings. They can absorb the vibrational energy of their surroundings. Some are more energetic in that they have a faster vibration, and some are more mellow and calming. The difference between carnelian and amthyst, for example. And stones can absolutely take on negative aspects of their environment. They can't hold malice or intent, but they can pick up the negative vibrations around them and that can influence the energy of the crystal itself. They can be cleansed, a sort of reset factory default, in a number of ways. They can also be programmed or charged to emit the vibration of a certain energy or emotion. I suppose it all depends on who has them, who had them before that, and what they were used for.
Seph is correct, but I wouldn't go so far as to say opposites. Opposites give the wrong impression. What is more accurate is to consider that what can be given can equally be taken away. That gives the illusion of opposing forces, when in truth it is the authority over a certain force, gifting it or taking it away.
