The Iron (Wu Qu, 武曲) star

What the classic Zi Wei Dou Shu Quan Shu (紫微斗数全书) says it is

The sixth star of the northern dipper, Metal, and the ruler of the Wealth palace. In the same palace as the Treasury (天府) there is long life. It exercises its authority across the twelve palaces, and its ground may be Exalted (庙), Strong (旺) or Fallen (陷). In a person it means a firm and decisive nature, with gladness and anger both in it, and blessing or calamity both possible. Meeting the trapped (囚) star in the Zhen, the east (震) palace it certainly means a broken undertaking and long delay. Running with the Hoard and the Steed (禄马), wealth is made in a distant province. Sharing the palace with the Wolf (贪狼), a mean and grudging person. With the Disruptor (破军) in the country of wealth, money reaches the hand and comes to nothing. Malefics gathered make calamity; benefics gathered make good fortune. Master Xiyi (希夷先生) says: The Iron (武曲) is Metal, governing long life in heaven and wealth in the reckoning. It fears being held down and badly placed, and welcomes the Hoard (禄存) governing with it. With the Moon (太阴) it shares authority; the Treasury and the Minister (天相) are its assisting stars; Wealth and Property are its particular charge. Harsh malefics, the Great Drain (大耗) and the trapped meeting in the Zhen, the east palace, and one certainly meets wood falling and thunder striking. The Disruptor and the Wolf meeting in the Kan, the north (坎) palace, and one drowns. Meeting the Hoard and the Steed, wealth is made in a distant province. Meeting the Wolf, the early years are unfavourable — hence the saying that Iron holding the Self is no light blessing, and that a Wolf does not open out for a young man. Well placed with the peach blossom (桃花) in the same palace, it profits itself and costs others. With the General (七杀) and the Flare (火星), wealth is taken by robbery. Meeting the Blade (擎羊) and the Millstone (陀罗), solitude and harm; meeting the Disruptor, honour is hard to show. With the Disruptor in the same place, and coming into either limit, it certainly means disputes. Broadly, the Iron holding the Self makes a person firm, strong and decisive; born under Yang Wood (甲) or Yin Earth (己) the blessing is thick, and one goes out a general and returns a minister. Getting the Wolf and the Flare breaking in as well, it is certainly an honoured pattern. It likes a person born in the north-west; those born in the south-east are ordinary and do not keep the ancestral estate. With the four malefics breaking in, solitude and poverty in one form or another, and a scar lengthens the years. A woman with many benefics is an honoured wife; with malefics breaking in, solitude and harm.

答曰：武曲北斗第六星，屬金，乃財帛宮主。與天府同宮有壽，其施權於十二宮分，其臨地有廟、旺、陷宮。主於人，性剛果決，有喜有怒，可福可災。若陷囚會於震宮，必為破主淹留之舉。與祿馬交馳，發財於遠郡。若貪狼同度，慳吝之人。破軍同財鄉，財到手而成空。諸凶聚而作禍，吉集以成祥。希夷先生曰：武曲屬金，在天司壽，在數司財。怕受制入陷，喜祿存而同政。與太陰以互權，天府、天相為佐貳之星，財帛田宅為專司之所。惡殺耗囚會於震宮，必見木壓雷震。破軍貪狼會於坎宮，必主投河溺水。會祿馬則發財遠郡。貪狼會則少年不利。所謂武曲守命福非輕，貪狼不發少年郎是也。廟樂桃花同宮，利己損人。七殺火星同宮，因財被劫。遇羊陀則孤克，遇破軍難顯貴。若與破軍同位，更臨二限之中，定主是非之撓。蓋武曲守命，主人剛強果斷，甲己生人福厚，出將入相。更得貪火沖破，定為貴格。喜西北生人，東南生人平常，不守祖業。四殺沖破孤貧不一，破相延年。女人吉多為貴婦，加殺沖破孤克。