In Hinduism, the tilaka or tilak (Sanskrit: तिलक tilaka; Hindustani pronunciation: [t̪ɪˈlək] tilak)[1] is a mark worn on the forehead and other parts of the body. Tilaka may be worn on a daily basis or for special religious occasions only, depending on different customs.

The tilaka symbolize the third eye, or mind's eye, that is associated with many Hindu gods and the idea of meditation and spiritual enlightenment. In the past, tilakas were usually worn by gods, priests, ascetics, or worshipers, but is now a common practice for most Hindus. It can express which Hindu tradition one follows. It may be made with sandalwood paste, ashes (vibhuti), kumkum, sindhoor, clay, or other substances. The pastes are applied to the forehead and in some cases to the upper part of the head.

The truth of the matter is this the true Tilaka can not be applied with stick on jewelry or powder

or any other substance it will come into existence   thru prayer on a prayer rug when the Muslim

and from what Ive seen Muslims diligently place there forehead to the earth in pray and after years

of repeating this act they achieve what is known as the true mark of the father on there forehead

and that's the only way to receive it anything else is fraudulent sorry people...to have to disappoint you

but its is known in Islam as the mark of prostration and that's the only way to get gods mark on your forehead

and if your not prostrating 5 times a day then you wont ever achieve this mark and anything else is fraudulent

see images of the true mark of god...at the bottom and this is how you get your third eye opened for real

lol get you one a prostration mark...

The mark is not physical. Those with a physical mark is because they are making sujud wrong and putting too much pressure on their forehead or the rug is hard such as one I pray on at work. In reality the mark is the mark of piety i.e., NUR.

I have seen many people who pray copious amounts and have no such mark.

see: http://muxlim.com/blogs/abumaalik/prostration-mark/