Isolated, the Jack of Diamonds represents the postman or, better said, the messenger. It also symbolizes a young soldier or an unfaithful servant (assistant, employee); sometimes a young blond man, traitor and of bad morals.
If the consultant is a young man, it is the announcement of new lovers.
If it is a young girl or a single woman, it is the certainty that, soon, a suitor will make himself known; he will be blond and pretty boy.
If, on the contrary, the consultant is married, he will soon learn of a somebody’s else marriage; but this card, surrounded by it, has many and varied meanings.

The Jack of Diamonds with a
Spade ♠: Treachery, infidelity.
Heart ♥: Certainty of marriage and news of birth.
Diamond ♦: Young risk-taking man, adventurer of misconduct.
Club ♣: Somebody will ask to borrow money from you.

Having on the left a
Spade ♠: A dark man you have every reason to fear.
Heart ♥: Love. Letter coming soon.
Diamond ♦: Null card.
Club ♣: Money that will be lost. Theft.

EXCEPTIONS.
The Jack of Diamonds, with the
King of Diamonds: News from a young adventurous man.
Between two sevens: News of a pregnancy.
Touching the Ten of Diamonds: Distant journey. (The other card touching it becomes null and void.)
Touching the ace of Clubs: News of an inheritance. (The other card touching it becomes null and void.)
Between two face cards: deceit, treachery, infidelity.
Between two aces: The Jack of Diamonds says nothing; he is absolutely silent.

Bad words, actions, travel.

The Eight of Diamonds having to right, a
Spade ♠: Distant travel without any profit.
Heart ♥: A journey full of pleasure.
Diamond ♦: Efforts without success.
Club ♣: Loss of money.

Having on the left a
Spade ♠: A friend’s slander.
Heart ♥: Wedding trip or trip to the city to attend a wedding.
Diamond ♦: Efforts without success.
Club ♣: Money found.

EXCEPTIONS.
Between two cards of the same value: Travel postponed.
Between two Hearts: Husband and wife will make steps to become closer.
Between two Clubs: Travel for very small inheritance or business gain.
Between two spades or two low cards of Diamonds: unsuccessful efforts.
Between the Queen of Clubs and the King of Spades: Disunion.
Between two Diamond figures; The card is null; it does not speak.

Happy boyfriend, Sincere lover, Slightly dangerous flatterer, Friendly, enterprising, skillful, brave young man; that is the meaning of this card taken in isolation.
This Jack or, better to say – Valet – has many particular meanings that are more or less favourable.
Isolated, pulled from a deck by a young girl or woman, he represents her fiancé, a dark, honest and good young man; but if he is between two spades, his family and friends will oppose the marriage. It will take place anyway, despite all the resistance.
For a young man, he represents his more successful and wealthier rival; but between two heart cards, this rival will be ousted.
For a divorced person or a widower, it’s the announcement of his/her next marriage.
Finally, by any other person, this card ensures complete success in everything they would do.

Having on the right a
Spade ♠: You will meet a young man who has just become rich or famous. This is your chance. Don’t waste it.
Heart ♥: An OK, but not great boyfriend or girlfriend. You can do better in love. However, if he or she is generous in bed and thinks of you, this omen might be misleading. Count all the heart cards that you draw. If you get many – maybe the other cards are trying to tell you something better about your Jack of clubs.
Diamond ♦: Wrong idea. Whatever you are stubbornly convinced and arguing about – take a second look.
Club ♣: Difficulties. – Delay of a marriage due to insufficient wealth or uncertain career.

Having on the left a
Spade ♠: New acquaintance of a pretty brown (brunet) boy, but very silly, although believing himself to be spiritual. Call spade a spade, and call stupid a stupid.
Heart ♥: Discreet love. – Beneficial friend.
Diamond ♦: Visit of a “bon vivant” friend, who will bring you joy and happiness.
Club ♣: Complete success in any business decision that you are agonising about.

EXCEPTIONS.
Between two Spades: Delayed marriage which will only take place after meeting and gaining the favour of the parents.
Between two Hearts: Rivalry that will not be fatal, but very very damaging. If you know who your rival is – strike first.