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Region

Sets
Classic
Supplemental
Curved and Round Bricks

423-4 LEGO Curved and Round Bricks

Name: LEGO Curved and Round Bricks
Brand: LEGO
SKU: 423-4
Rating: 4.70 (7 reviews)

Images 1

Set Value (New/Sealed)

This chart represents the current new/sealed value of the set Curved and Round Bricks since June 2016. High accuracy

LEGO 423-4 Curved and Round Bricks was a 50 piece Classic set released in 1966. This was a parts set branded under LEGO System. The current value for a new and sealed Curved and Round Bricks is estimated at $42, with an average annual growth of approximately 6%. Current used prices for Curved and Round Bricks range from $34 to $39, depending on the set's condition, with an average price of $35 for those in good overall condition.

Curved and Round Bricks has become a rare set, as set 423-4 has not been available for sale online or in retail in new and good condition for over one year. The current value of this set might be slightly higher than our current estimate. The last brand new Curved and Round Bricks was sold on eBay.

There are currently no new/sealed listings available for Curved and Round Bricks at this time.

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Related Sets


	923 50 Bricks Curved and Round Theme / Subtheme Classic / Supplemental Year 1969 Pieces 50 Availability Retired Buy this set at Bricklink	Retail $0.50 Value $31.20 Growth +6140.0% Annual growth 4.1% I own this set I want this set

Sets in Classic / Supplemental


	471 Tiles Theme / Subtheme Classic / Supplemental Year 1966 Pieces 52 Availability Retired Buy this set at Bricklink	Retail $0.50 Value $26.98 Growth +5296.0% Annual growth 4.7% I own this set I want this set

	434 50 Lettered Bricks Theme / Subtheme Classic / Supplemental Year 1966 Pieces 50 Availability Retired Buy this set at Bricklink	Retail $0.50 Value $50.64 Growth +10028.0% Annual growth 6.9% I own this set I want this set

	437 50 Numbered Bricks Theme / Subtheme Classic / Supplemental Year 1966 Pieces 50 Availability Retired Buy this set at Bricklink	Retail $0.50 I own this set I want this set

	421 1x2 Bricks Theme / Subtheme Classic / Supplemental Year 1966 Pieces 44 Availability Retired Buy this set at eBay Bricklink	Retail $0.50 Value $19.60 Growth +3820.0% Annual growth 5.2% I own this set I want this set

	487-2 1x1 Bricks with Numbers Theme / Subtheme Classic / Supplemental Year 1966 Pieces 44 Availability Retired Buy this set at Bricklink	Retail $0.50 Value $43.14 Growth +8528.0% Annual growth 4.1% I own this set I want this set

	488 1x1 Bricks with Letters Theme / Subtheme Classic / Supplemental Year 1966 Pieces 44 Availability Retired Buy this set at Bricklink	Retail $0.50 Value $89.22 Growth +17744.0% Annual growth 5.6% I own this set I want this set

	470 1x1, 1x2, 2x2, 2x3, 2x4 Plates Theme / Subtheme Classic / Supplemental Year 1966 Pieces 39 Availability Retired Buy this set at Bricklink	Retail $0.50 Value $52.70 Growth +10440.0% Annual growth 5.7% I own this set I want this set

	481-5 Slopes Regular, Double, Angle, Valley and Corner Red Theme / Subtheme Classic / Supplemental Year 1966 Pieces 34 Availability Retired Buy this set at Bricklink	Retail $0.50 Value $20.00 Growth +3900.0% Annual growth 5.3% I own this set I want this set

	481-6 Slopes Regular, Double, Angle, Valley and Corner Blue Theme / Subtheme Classic / Supplemental Year 1966 Pieces 34 Availability Retired Buy this set at Bricklink	Retail $0.50 Value $28.66 Growth +5632.0% Annual growth 5.9% I own this set I want this set

	420-4 2x2 Bricks Theme / Subtheme Classic / Supplemental Year 1966 Pieces 33 Availability Retired Buy this set at Bricklink	Retail $0.50 Value $19.20 Growth +3740.0% Annual growth 2.7% I own this set I want this set

	422 1x1, 1x2, 1x4, 1x6, 1x8 Bricks Theme / Subtheme Classic / Supplemental Year 1966 Pieces 28 Availability Retired Buy this set at Bricklink	Retail $0.50 Value $19.60 Growth +3820.0% Annual growth 5.2% I own this set I want this set

	423-3 Curved and Round Bricks Theme / Subtheme Classic / Supplemental Year 1966 Pieces 28 Availability Retired Buy this set at Bricklink	Retail $0.50 Value $28.95 Growth +5690.0% Annual growth 5.9% I own this set I want this set

	419-3 2x3 Bricks Theme / Subtheme Classic / Supplemental Year 1966 Pieces 25 Availability Retired Buy this set at Bricklink	Retail $0.50 Value $16.52 Growth +3204.0% Annual growth 4.9% I own this set I want this set

	480-6 Slopes and Slopes Double 2x4 Red Theme / Subtheme Classic / Supplemental Year 1966 Pieces 23 Availability Retired Buy this set at Bricklink	Retail $0.50 Value $25.00 Growth +4900.0% Annual growth 5.7% I own this set I want this set

	480-7 Slopes and Sloped Double 2x4 Blue Theme / Subtheme Classic / Supplemental Year 1966 Pieces 23 Availability Retired Buy this set at Bricklink	Retail $0.50 Value $28.90 Growth +5680.0% Annual growth 5.9% I own this set I want this set

	482-3 Slopes and Slopes Double 2x2 Red Theme / Subtheme Classic / Supplemental Year 1966 Pieces 22 Availability Retired Buy this set at Bricklink	Retail $0.50 I own this set I want this set

	482-4 Slopes and Slopes Double 2x2 Blue Theme / Subtheme Classic / Supplemental Year 1966 Pieces 22 Availability Retired Buy this set at Bricklink	Retail $0.50 Value $19.32 Growth +3764.0% Annual growth 5.2% I own this set I want this set

	418-3 2x4 Bricks Theme / Subtheme Classic / Supplemental Year 1966 Pieces 21 Availability Retired Buy this set at Bricklink	Retail $0.50 Value $38.54 Growth +7608.0% Annual growth 6.4% I own this set I want this set

	481-3 Slopes and Slopes Double 2x3 & 2x1 Red Theme / Subtheme Classic / Supplemental Year 1966 Pieces 21 Availability Retired Buy this set at Bricklink	Retail $0.50 Value $27.67 Growth +5434.0% Annual growth 5.8% I own this set I want this set

	481-4 Slopes and Slopes Double 2x3 & 2x1 Blue Theme / Subtheme Classic / Supplemental Year 1966 Pieces 21 Availability Retired Buy this set at Bricklink	Retail $0.50 Value $19.32 Growth +3764.0% Annual growth 5.2% I own this set I want this set

	420-3 2x2 Bricks Theme / Subtheme Classic / Supplemental Year 1966 Pieces 20 Availability Retired Buy this set at Bricklink	Retail $0.50 Value $20.18 Growth +3936.0% Annual growth 5.2% I own this set I want this set

	421-2 2 Eights 2 Sixes 2 Fours 8 Twos 6 Ones Theme / Subtheme Classic / Supplemental Year 1966 Pieces 20 Availability Retired Buy this set at Bricklink	Retail $0.50 I own this set I want this set

	459 1x1x1 Windows Red or White Theme / Subtheme Classic / Supplemental Year 1966 Pieces 20 Availability Retired Buy this set at Bricklink	Retail $0.50 I own this set I want this set

	483-4 Angle Valley and Corner Slopes Red Theme / Subtheme Classic / Supplemental Year 1966 Pieces 20 Availability Retired Buy this set at Bricklink	Retail $0.50 Value $24.59 Growth +4818.0% Annual growth 5.6% I own this set I want this set

	483-5 Angle Valley and Corner Slopes Blue Theme / Subtheme Classic / Supplemental Year 1966 Pieces 20 Availability Retired Buy this set at Bricklink	Retail $0.50 I own this set I want this set

My Collection

I own this set

I want this set

Set Details

Set number

423-4

Name

Curved and Round Bricks

Theme

Classic

Subtheme

Supplemental

Year

1966

Availability

Retired

Pieces

50 (PPP $0.01)

Set PricingVery Rare

Retail price

$0.50

New/Sealed

Value

$42.32

Growth

+8364.00%

Annual growth

+5.62%

90-day change

2.29%

Used

Value

$35.13

Range

$34.46 - $39.09

Quick Buy

eBay

Check

Bricklink

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*Listings are for new/sealed sets.

Set Predictions

New/Sealed

Today's value

$42.32

1 year forecast

$44.70+5.62%

5 year forecast

$54.10+27.85%

$54

$56

423-4 Curved and Round Bricks is projected to be valued between $54 - $56 within five years.

Set Facts

This was similar to set 923-1 50 bricks, curved and round.

Regional Retail Prices

United States

$0.50

United Kingdom

£1.95

Curved and Round Bricks Reviews

7 ratings

4.7

Collectors

Investors

Subtheme Analysis

Classic / Supplemental

Sets

140

Years

1960 - 1971

Annual growth

+5.72% (this set +5.62%)

This set's annual growth (CAGR) vs. subtheme

Community Stats

Curved and Round Bricks currently ranks #127 out of the top most owned sets in Classic Supplemental.

#1Lighting Bricks with Color Filters

#2Gray Baseplate

#3Small Wheels with Axles

#412 Doors and 5 Hinges

#5Large Wheels with Axles

#127Curved and Round Bricks

#1281x6x3 Window with Frame

#1291x6x2 Double-Pane Window in Frame with Shutters

About Classic Supplemental

Starting in the 1950s LEGO began individual parts sales, a practice that began with the Ferguson Tracktor in 1951. LEGO would supply dealers with wooden parts boxes and refill packs. These individual part sales would continue, at least in some markets, into the late 1950’s.

Supplemental consists of 140 sets that ran from 1960 to 1971. As of today, 890-2 Lockable Storage Box is the most valuable Supplemental set with an estimated new/factory sealed value of $357.

Set Pricing Models

BrickEconomy uses a number of methods to determine the value of a set.

New/Sealed

Machine Learning/AI Model

Value (today)

$42.32

Value (in a year)

$44.70

Value (in 2 years)

$47.08

Accuracy

0.820000 High

Statistical Model

Value (today)

$45.91

Value (in a year)

$48.34

Value (in two years)

$50.77

Accuracy

0.464145 Low

Used

Machine Learning/AI Model

Value (today)

$35.13

Value (low range)

$34.46

Value (high range)

$39.09

Accuracy

0.765000 High

To learn more about how we calculate pricing and forecasting, check out our article on BrickEconomy’s Approach to LEGO Pricing and Future Value Predictions.

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