The Four of Disks
The Lord of Power represents the time when we achieve a stable level of material balance - at least for that moment in time. At the purely mundane level, it might come up after we had settled into a new home, or undertaken major improvements. The card is, at this level, much concerned with asset security and material bounty.
One thing to bear in mind about attaining the mundane value of this card - though you have achieved one level of material stability, you cannot either cling to this, nor take it for granted. Become too smug and you'll find yourself losing the sense of safety and balance which has occurred. The human being is not naturally given to stagnation...
On a more spiritual level this card holds sway over crystals and semi-precious stones - it might be hard to see the cross-reference to the asset security I mentioned in the previous paragraph - but on a mundane level, we're often talking bricks-and-mortar and the security derived from being safe within our homes - at this more subtle level, we're still talking rocks!! But this talking we're relating to the amount of energy we can all gain from crystal-work.
Some crystals teach us calmness, or emotional balance, simply by giving off their unique energies. Other crystals can be programmed to assist us in various self-development tasks, and in protection, healing and cleansing. So if this card comes up in your reading with cards like the Hierophant, the Star, the Moon or the Priestess, consider that perhaps you'd help yourself with a little crystal work!