These opening bids were devised and developed by Mr. Gordon Bower of Fairbanks, Alaska, United States, as a variation on systems, which employed multiple strong/weak 1 Club openings.

As a geologist, Mr. Gordon Bower appropriately named his version, which circumvented the 1 Club strong opening bid as being percentage-wise too high in high card point requirements, the Feldspar Bidding System. Mr. Gordon Bower, based on mathematical percentages, lowered his requirement for a 1 Club opening bid by at least a King in order to bid more frequently and to by-pass the so-called catch-all bid of 1 Diamond.

Feldspar is a designation taken from Old German and means any of a group of abundant rock-forming minerals occurring principally in igneous, plutonic, and some metamorphic rocks, and consisting of silicates of aluminum with potassium, sodium, calcium, and, rarely, barium. About 60 percent of the earth's outer crust is composed of feldspar.

This version gained local and regional popularity and was only played on a limited basis. The opening bids are shown in the schmatic below. Mr. Gordon Bower TiagaBridge.

Note: Mr. Gordon Bower has authored an online write-up about How Light Should An Opening Bid Be, which has also only been preserved and archived on this site in .pdf file format for future reference. This article is presented in three different parts: Part 1, Part 2, and Part 3.

Opening Bids Only

Bid		Strength		Meaning
1 :		13-16 high card points		Shows a 5-card plus Club suit, or
		17-19 high card points		shows balanced shape, or
		19+ high card points		promises a one- or two-suited holding, or
		23+ high card points		shows balanced shape.
1 :		13-18 high card points		Shows a 4-card plus Diamond suit.
1 :		11-18 high card points		Shows a 5-card plus Heart suit.
1 :		11-18 high card points		Shows a 5-card plus Spade suit.
1 NT:		14-16 high card points		Shows balanced shape.
2 :		11-14 high card points		Distribution: 4-4-4-1 or 5-4-4-0, or
		19+ high card points		Distribution: 4-4-4-1 or 5-4-4-0.
				Subsequent rebids show point range.
2 :		11-14 high card points		Shows distribution: 4-4, 5-5, or 6-6 in both Major suits, or
		15-18 high card points		shows distribution: 4-4-4-1 or 5-4-4-0, or
		19+ high card points		shows distribution: 4-4, 5-5, or 6-6 in both Major suits.
				Subsequent rebids show point range.
2 :		6-12 high card points		Shows 6 Hearts.
2 :		6-12 high card points		Shows 6 Spades.
2NT:		20-22 high card points		Shows balanced shape.

Any first response after a 1 Club opening of 1 Diamond indicates a weak holding of 0-5 points and other responses are considered natural. Following a 2 Club opening bid, the first response of 2 Diamonds is one-round forcing whereas a first response of 2 No Trump is game-forcing.

Following a 2 Diamond opening bid, the first response of 2 No Trump is one-round forcing. Any jump shift by the responder, at the first chance to bid and possibly by an already passed hand, are Weak Jump Shifts and non-forcing.

If you wish to include this feature, or any other feature, of the game of bridge in your partnership agreement, then please make certain that the concept is understood by both partners. Be aware whether or not the feature is alertable or not and whether an announcement should or must be made. Check with the governing body and/or the bridge district and/or the bridge unit prior to the game to establish the guidelines applied. Please include the particular feature on your convention card in order that your opponents are also aware of this feature during the bidding process, since this information must be made known to them according to the Laws of Duplicate Contract Bridge. We do not always include the procedure regarding Alerts and/or Announcements, since these regulations are changed and revised during time by the governing body. It is our intention only to present the information as concisely and as accurately as possible.