Theme: TWICE AS NICE (Stars were accidentally omitted from theme clues)
17. "Two Tahitian Women" painter: PAUL GAUGUIN.
23. 1965 Beau Brummels hit with the line "It seemed so funny to me": LAUGH LAUGH.
38. Southern lights: AURORA AUSTRALIS.
51. Reuben ingredient: SAUERKRAUT.
63. 13th/14th-century Mongol Empire region ... and an elemental hint to what's found twice in each answer to a starred clue: GOLDEN HORDE.
The symbol for gold is AU, and each theme answer contains two AU's.
Across:
1. Small earring: STUD. Ears are often pierced using a piercing gun with gold (AU) STUDs.
5. Mercedes line: E CLASS.
11. Magazine with a satirical "fold-in" back cover: MAD. Here's one from 2008.
14. Bear in two constellations: URSA.
15. Bits of dust: SPECKS.
16. Curling surface: ICE. Curling, the sport. Sneaky clue, but with three letters what else could it be?
19. Testing site: LAB.
20. Minute: SMALL. Another sneaky clue.
21. SFO incoming flight: ARR. Air travel - not too much of that these days.
22. Narrow cut: SLIT.
27. Neverland pirate: SMEE. From Peter Pan.
28. Snap, crackle and pop: NOISES. Again with the sneaky clues!
32. CPR expert: EMT.
35. Media org. that tweets the Declaration of Independence on July 4: NPR. I listen every day, but did not know that.
37. Partner of each: EVERY.
43. H.G. Wells genre: SCIFI.
44. Moo __ gai pan: GOO. Chinese dish with chicken and mushrooms.
45. Kin of -kin: LET. This took a little thought. -kin as a suffix, like in munchkin, and -let, as in piglet. They are both diminutives.
46. Yet: THOUGH.
48. Zodiac transition point: CUSP.
55. Adhesive strip: TAPE.
58. Bygone telecom co.: MCI. The end of a telecom icon.
59. Waited in line, say: STOOD. Six feet apart.
62. "Ben-__": HUR.
66. The Nixon years, e.g.: ERA. Don't remember seeing this clue before.
67. Capital west of Krakow: PRAGUE. Capital and largest city in the Czech Republic, the 13th largest city in the European Union and the historical capital of Bohemia.
68. Tiny amt. of time: NSEC. A nanosecond (ns or nsec) is one billionth (10-9) of a second and is a common measurement of read or write access time to random access memory (RAM).
69. "Great news!": YAY.
70. Autumn blooms: ASTERS.
71. Fair: SO-SO.
Down:
1. Enjoys an evening meal: SUPS.
2. Magic Kingdom people mover: TRAM.
3. Customary: USUAL.
4. "Who Shot J.R.?" show: DALLAS.
5. That, in Tijuana: ESA.
6. Apple core?: CPU. Nice clue.
7. Sanctioned: LEGAL.
8. Honda luxury brand: ACURA.
9. Vail trail: SKI RUN. Colorado.
10. Common ID: SSN. Social Security Number.
11. Pepper grinder: MILL.
12. Berry from South America: ACAI. Everything you need to know.
13. It's outstanding: DEBT. Lol.
18. In a funk: GLUM.
22. Hindu deity known as the Destroyer: SHIVA.
24. Rowlands who won an Emmy for playing Betty Ford: GENA. The Betty Ford Story.
25. Air filter acronym: HEPA. "High Efficiency Particulate Air" or "High Efficiency Particulate Arrestance."
26. Suffix with movie or church: GOER.
29. What some bears do: SELL. A bear is an investor who believes that a particular security, or the broader market is headed downward and may attempt to profit from a decline in stock prices. Bears are typically pessimistic about the state of a given market or underlying economy.
30. Keystone State port: ERIE. Pennsylvania.
31. Part of CNS: Abbr.: SYST. Central Nervous System.
32. Dawn direction: EAST.
33. Greatly: MUCH.
36. Throw __: RUG.
39. Beneficial: OF USE.
40. Latvian birthplace of Baryshnikov: RIGA. Wikipedia.
41. Bit of footwear: SOCK.
42. __ de force: TOUR.
47. Indulges: HUMORS.
50. Deceptions: PUT ONS.
52. Razzle-dazzle: ECLAT. Brilliant display or effect.
53. Blue __ Mountains: RIDGE.
54. Trunk: TORSO.
55. "So __ say": THEY.
56. Ambience: AURA.
57. Use rosary beads, say: PRAY.
60. Poetic tributes: ODES.
61. Geometric art style: DECO.
63. Transcript fig.: GPA. Grade Point Average.
64. Prefix with Asian: EUR.
65. Wii forerunner, briefly: NES.