Apollon himself manifests, like Zeus with Cronos, as heir of Koios through his mother Leto. His very own most sacred image found at every home was that of a tall upright (usually black, but I am uncertain if it was of a natural pigmentation of stone or if it was coated with substance to give it a black appearance) where Apollon was worshiped. Where temples adored Apollon in various forms, his most ancient and common household form continued to be the simple stone where he bestowed his protection upon the household and where he received daily and monthly offerings and offering of any auspicious occasion, poured over his form and garlands draped from this simple aniconic form.
While there have been plaques and other simple images to of the god, the common appearance of the god as a stone through Hellas and into Rome and throughout Europe by Rome, has to be the most universal and most worshiped and beloved form of the god. It is the god without containment into true form, he who is formless and ancient. He who delights in the pouring streams and fountains with which a number of them are sacred to them, he who is the uplifting column of light illuminating all things, he who is the pole around which all of the heavens and the turn of seasons and years turns O lord of time who is both as the sun and the beauty of the moon, he who is the kithara player—and as such the leader of the holy dance of time as each song he plays summons for the seasons in their ageless dances. This is both his generative form and his destructive form this manner. He is both as the erect spear (and the miniature form as arrows) that his very column like form bears at Amyclaeus, the column of fire uplifting, the column of life bringing forth generation for which people may imagine that it is has a slight phallic resemblance even though it is not phallus. This simple form, the healing lord of the springs, the fiery destroyer/protector, the generator and protector of young, the upright leader of the dance and pole of the turning heavens, in this form he is all these things at once and more. There has too been some argument that the doorway offerings to Hekate or Artemis Prothyria may have been offered in the base of the lingam as to which in Rome it makes sense especially to see a youth and maiden on a temple plague attending both on the adornment of the Agyieus stone. Although we do not find any direct reference to either of these goddesses with the base of the Agyieus of Apollon, although perhaps a vague reference to Hekate and two great pillars (Hermes and Apollon Agyeius respectively) it is easy to see how these goddesses can be so associated. Especially when we see imagery of Artemis as pouring offering to the bowl of her twin and their inseperable union with each other. Understanding the stone as a column of light and Artemis as a torch bearer, that which bears the light, is perhaps a very significant metaphor for the imagery of the stone secured.
In the Hindu narrative likewise we find Siva, the lord of the column of which is his true form, and of which Brahma and Vishnu competed to scale its great height to remove a flower from the top, a top that is infinite and unreachable except to those that by grace he allows. Although, like Apollon in Hellas, Siva has many beautiful images throughout India, we still find the most common and sacred is the formless god as the lingam. Large beautiful lingams grace the temples transfixed and unmoveable, and small ones in the households blessing the householder and wife, blessing the children. He to dwells inseparable from his union with Sakti/Parvati. It is to this form that his offerings are provided, ghee, water poured, honey, milk. Garlands of rudraska beads and flowers adorn his form. His blessing pour forth, O great column and lord of time. At his winter festival we find this form symbolically replicated as its true form as a column of light of which the stone form is but a stable permanent reflection. At this festival a great bon fire is created which spires to the heavens. Videos can be found online of this and it is an awe inspiring sight to behold this great shift of light connection the heavens and earth. Massive and uncontainable, without beginning or end. The upright column is continuous without limit.
And so my lingam/Agyieus stone is to me the most beautiful image of my god. My lord Siv-Apollon free form limitation, ever dancing, ever churning, rotating forth all things, from who the coolest blessed water gush forth by his headed is rooted in the heavens even as the hottest of fires of illumination emanate from him at every point as arrows shooting from him. Siv-Apollon is greatest of archers, shooting forth the greatest distances from afar, he is both motionless and in motion, he is leading forth the motion of all life and living beings, of beasts and men, and reuniting them again.
Most blessed lord, I will ever give most devout reverence to this form of yours O Siv-Apollon! I will dress you with flowers, and pour offerings to run upon you for your delight, perfume you with sweet smoke of incense. You are the door to all things blessed lord and with adoration will always bow before you!