The Compendium of Caraka 6.1.3

Now we shall expound the quarter of rejuvenatives entitled 'Hand-Harvested'.

Having used it, the self-controlled were freed from fear of fatigue, disease, and old age;
by its power, possessed of great strength, they practiced asceticism as long as they wished.
Brahmā created this rejuvenative lasting a thousand years,
which relieves old age and disease, and confers strength upon the intellect and sense faculties.
(Thus ends the iron-and-āmalakī rejuvenative of Brahmā.)

By asceticism, celibacy, meditation, and tranquility,
by the proper use of rejuvenatives, and by an appropriate lifespan,
the great sages of old endured; for no rejuvenative succeeds
for the rustic, for those engaged in other pursuits, or for those whose minds are not self-controlled.
Subsisting on milk for a year, one should dwell always among cows,
meditating mentally on the Sāvitrī, celibate, with restrained senses.
At the end of the year, on the full-moon day of Pauṣa, Māgha, or Phālguna,
having fasted for three days of the bright fortnight, one should enter an āmalakī grove.
Having climbed a tree rich with large fruits, grasping a fruit on a branch
with one's hand, one should remain reciting the sacred syllable until the arrival of the nectar of immortality.
For at that moment the nectar of immortality surely dwells in the āmalakī for an instant;
[the fruits] become sweet like sugar and honey, oily, and soft
owing to union with the nectar of immortality. As many of them as one may eat,
for that many thousands of years one will live, restored to youth.
Having reached full repletion with them, he becomes like an immortal,
and Fortune, the Vedas, and embodied Speech attend upon him of their own accord.
(Thus ends the pure āmalakī rejuvenative.)

In the decoction of triphalā, in cow's urine, in salt-water,
and successively in the alkali of ingudī and the alkali of kiṃśuka,
one should quench sheets of sharp iron brought to the color of fire,
four finger-breadths long and as thin as the height of a sesamum seed.
Knowing them to have become dark like collyrium, one should reduce them to fine powder.
Those powders, mixed with honey and the juice of āmalakī,
resembling an electuary and kept in a pot seasoned with ghee,
should be placed for one year in a mound of barley grains.
The wise man should stir it every month, mixing it thoroughly everywhere.

At the conclusion of the year, its administration is with honey and ghee
every morning, taking account of strength; and when it is digested, wholesome food [is taken].
This very procedure is proclaimed for [all] metallic preparations.
Neither by trauma nor by illnesses, neither by old age nor by death
can he be overcome; he possesses the vitality of an elephant and always has exceedingly strong sense faculties.
Wise, renowned, successful in speech, retaining what he has heard, and possessing great wealth
becomes the man who uses this iron rejuvenative for a year.
By this very procedure, an established administration of gold and of silver,
which brings about extension of lifespan and cures all diseases, [is accomplished].
(Thus ends the rejuvenative of iron and other metals.)

Aindrī, matsyākhyaka, brāhmī, vacā, brahmasuvarcalā,
pippalī, rock salt, gold, śaṅkhapuṣpī, viṣa, and ghee:
of these, three barleycorn-weight portions each, except for gold, ghee, and viṣa;
of gold there should be two barleycorns, and of sesamum seed [weight] of viṣa,
and one pala of ghee should be added; one should administer it all together.
After it is digested, food mixed with plenty of ghee and honey is recommended.
This allays old age and disease, is supreme in producing memory and intellect,
promotes lifespan, is nourishing, auspicious, and clarifies voice and complexion.
This is a supreme producer of ojas, the perfected rejuvenative of Indra;
neither sorcery, nor misfortune, nor poison, nor sickness prevails over him.
Vitiligo along with kuṣṭha, abdominal enlargements, abdominal lumps, spleen disease, chronic irregular fever,
and diseases that rob intellect, memory, and knowledge, as well as exceptionally strong vāta disorders, are allayed by it.
(Thus ends the rejuvenative of Indra.)

The fresh juice of maṇḍūkaparṇī should be used; powder of yaṣṭīmadhuka with milk;
the juice of guḍūcī with its roots and flowers; and indeed the paste of śaṅkhapuṣpī should be used.
These rejuvenatives bestow long life, destroy sickness, and promote strength, digestive fire, complexion, and voice;
they are promoters of intellect, and śaṅkhapuṣpī in particular is an intellect-promoter.
(Thus ends the intellect-promoting rejuvenatives.)

Five, eight, seven, or ten pippalīs with honey and ghee,
one seeking the qualities of a rejuvenative should use for one year.

Eating three [pippalīs] each in the forenoon and before a meal,
pippalīs soaked in kiṃśukakṣāra and fried in ghee,
mixed with honey, should be used by one desiring the qualities of a rejuvenative
to conquer cough, consumption, wasting, dyspnea, hiccup, throat diseases,
hemorrhoids, disorders of the duodenal tract, jaundice, irregular fever,
hoarseness, chronic rhinitis, swelling, abdominal lumps, and vātabalāsaka.
(Thus ends the pippalī rejuvenative.)

By gradual increase over ten days, adding ten pippalīs a day,
one should increase them with milk, and reduce them again in the very same way.
When each [dose] is digested, one should eat sixty-day rice with milk and ghee.
This rejuvenative regimen consists of a thousand pippalīs.
Ground into a paste, they are to be consumed by the strong; boiled as a decoction, by men of medium strength;
and made into a powder, by those of lesser strength, according to dosas and disorders.
The ten-pippalī [course] is the best; the six[-pippalī course] is declared intermediate;
that course which has an extent of three is the least, and it is for the weak.
Nourishing, beneficial to the voice, life-promoting, destroying splenic enlargement and abdominal swelling,
arresting aging, promoting intellect is the rejuvenative of pippalīs.
(Thus ends the gradually increasing pippalī rejuvenative.)

At the end of digestion, one abhayā; before a meal, two bibhītakas;
and after eating, four āmalakīs with honey and ghee:
using this rejuvenative of triphalā for one year,
one will live a full hundred years, ageless and free from disease.
(Thus ends the triphalā rejuvenative.)

One should coat a new iron vessel with the paste of triphalā;
one should drink that coating, kept for a day and night, diluted in honey-water.
When it is digested, food with plenty of unctuous substance is recommended.
From practicing this for a year, one will live a hundred years, ageless and free from pain.
(Thus ends another triphalā rejuvenative.)

Combined with madhuka, tugākṣīrī, pippalī, honey, ghee,
and sugar, triphalā is an accomplished rejuvenative.

(Thus ends another triphalā rejuvenative.)
With all base metals, gold, vacā, honey, and ghee,
and with viḍaṅga, pippalī, and salt, triphalā,
used for a year, bestows intellect, memory, and strength;
it grants longevity, is auspicious, and destroys old age and disease.
(Thus ends another triphalā rejuvenative.)
Not sour, astringent, and pungent in post-digestive effect is śilājatu;
neither excessively hot nor cold, its origin is from four minerals:
from gold, silver, copper, and from excellent black iron.
It is a rejuvenative when [taken] according to rule, aphrodisiac, and curative of disease.
Thoroughly soaked in decoctions that destroy vāta, pitta, and kapha,
either with all together or each one individually, it attains supreme potency.
Thrown in and taken out, it should be thrown into the warm liquid again;
by this procedure its soaking lasts for seven days.
In conjunction with powdered metals according to the method stated earlier,
that, drunk with milk, will grant a long life accompanied by happiness,
allaying old age and disease, eminently producing bodily firmness,
bestowing intellect and memory, auspicious; living on milk, one should use it.
Its administration is of three types, designated as superior, middling, and inferior:
seven weeks, three [weeks], and one week.
Its dose is considered threefold: a pala, half a pala, and a karṣa.
Hereafter I shall explain the distinctions of its origin along with the method.
When heated by the sun, mountain ores of gold and the like exude
a soft, smooth, clear excretion resembling lac; that is śilājatu.
That which is sweet and bitter, resembling a hibiscus flower,
pungent in post-digestive effect, and cool is the exudation of gold.

That of silver is pungent, white, cool, and digests sweet.
That of copper resembles a peacock's neck, is bitter, hot, and digests pungent.
That, however, which looks like guggulu, is bitter with salt,
pungent in post-digestive effect, and cool, is from iron, and is the best of all.
All have the smell of cow urine and are suited for all procedures,
but for the administration of rejuvenatives, the last is superior.
In vāta-pitta, śleṣma-pitta, kapha, and in all three respectively,
the excretions arising from the minerals gold and the like are particularly praised.
During regimens of śilājatu, one must avoid foods causing burning and heavy foods;
at all times, however, one must completely avoid horsegram.
For they, being exceedingly incompatible, are observed in the world
to be the foremost splitters of stone; therefore, their use is prohibited.
Milk, buttermilk, meat soups, pulses, water, urine, and various decoctions
are commended for stirring śilājatu; they should be used after examining the purpose.
There is no curable disease on earth which that called stone cannot forcefully conquer;
administered according to rule at appropriate times, it also grants abundant energy to the healthy.