Yes, anyone can touch your crystals as long as you know how to cleanse and recharge the energy.
i) cleanse/ discharge
ii) recharge/ restore/ strengthen your own energy field
iii) rebirth / refresh your energy level with new downloads
The myth that one is not allowed to touch or hold other people’s crystals and vice versa makes an assumption that the person who has a different energy field will change or damage the energy field of your crystal; or perhaps takes away the healing properties.
That myth in fact is merely a generic advice for beginners who are not introduced to maintaining the energy of their own crystal.
In fact, touch is not the only factor affecting the energy of the crystals. Other factors such as yourself, usage of the crystal itself, the surroundings and Divine’s energy movement plays a major role. Thus, the most appropriate solution is to learn to maintain your crystal instead of fearing intrusion
Related article
CLEANSE AND CHARGE YOUR CRYSTAL/ STONE
http://xanxann.blogspot.com/2010/06/cleansing-crystal-stone.html
http://xanxann.blogspot.com/2010/06/cleansing-crystal-stone.html
CAN YOU CHARGE ENERGY OF SOMEONE ELSE'S
STONEhttp://xanxann.blogspot.com/2012/04/can-you-charge-someone-elses-stone.html