Although the power of a Witch comes not from outside objects but from spiritual/mind strength and abilities, many Witches will use reagaments and other supplies to aid them with their majjik. Also, you need things to make potions in and with.
Reagament is a word not commonly used today, and most dictionaries don't recognize it. Reagaments are commonly herbs, but some of them include:

• Beneficial herbs

These herbs would be used in potions for good reasons, including to heal, to bring good luck, to strengthen, etc. They can be found by looking at them in an non-majjik perspective, and the herbs that do you good like healing or nutrients are beneficial.

• Harmful herbs

Used to make potions that can poison, bring back luck, wound, etc. Often, these include poisonous berries. One common herb is a horseradish root. To find these, look in a non-majjik perspective. If they cause you harm or something bad, they are harmful.

• Neutral Herbs

Herbs that neither bring bad or good a person - herbs that outside of majjik, do nothing, but have a magical value. Used for potions that are neither beneficial or bad(i.e.-something to bring rain, or to get someone to leave you alone.) Find these by 'feeling' the majjik.

• Dragon scales

A scale given freely from a dragon. Depending on if the dragon, can be negative, positive, or neutral. If a dragon has done good deeds, it will be positive, if they did bad deeds it will be negative, and if they do both it would be neutral.

• Moon Crystals

A crystal named for its beauty and silver colour like the moon, along with the cold light of the moon it reflects when placed in moonlight.

• Viper's Fang

The poison and fangs stolen by vipers without permission. Negative.

• Dust

Dust from the earth under a tree struck by lightning or burned. Neutral

• Wolf, Bear or Tiger Fur

Fur taken from a wolf, bear or tiger (depending on where you live) with permission. Positive.

There are many, many more reagaments out there, but these are the most common few.